Vitamin B12 and plant-based diets

It’s not uncommon to read newspaper headlines about nutrient deficiencies from vegetarian or vegan diets – people love good news about their bad habits.

When you scratch beneath the surface of such headlines, though, it usually becomes obvious that the individual concerned wasn’t eating enough food in general or was suffering from another health condition.

Nevertheless, vitamin B12 deficiency is often quoted as a reason for avoiding plant-based or vegan diets.

Jane Philpott Cooking for Health

Plant-based dishes by Jane Philpott at

So is this justified?

Please read on if you’re interested in finding out.

What is vitamin B12 and why do you need it?

Vitamin B12, also called cobalamin, is a cobalt-containing water-soluble B vitamin.

Vitamin B12

It’s one of eight B vitamins, all of which help the body convert food (carbohydrates) into fuel (glucose), which is used to produce energy.

These B vitamins, often referred to as B complex vitamins, also help the body use fats and protein. B complex vitamins are needed for healthy skin, hair, eyes, and liver. They also help the nervous system function properly.

Vitamin B12 is an especially important vitamin for maintaining healthy nerve cells, and it helps in the production of DNA and RNA, the body’s genetic material.

Vitamin B12 also works closely with vitamin B9, also called folate or folic acid, to help make red blood cells and to help iron work better in the body.

Folate and B12 work together to produce S-adenosylmethionine (SAMe), a compound involved in immune function and mood.

Vitamins B12, B6, and B9 work together to control blood levels of the amino acid homocysteine. High levels of homocysteine are associated with a number of chronic health conditions, including heart disease, dementia and multiple sclerosis. Researchers aren’t sure whether homocysteine is a cause of these conditions or just a marker that indicates someone may have such a condition.

Vitamin B12, or cobalamin, belongs to a family of closely related chemicals, called corrinoids, some of which are biologically inactive in humans. The inactive versions are sometimes referred to as pseudovitamin B12 (1).

The two vitamin B12 coenzymes known to be metabolically active in mammalian tissues are 5-deoxyadenosylcobalamin and methylcobalamin.

How much vitamin B12 do you need?

Dietary guidelines for intake of vitamin B12 vary from country to country.

In the US, Australia and New Zealand the guideline is 2.4 µg (micrograms) per day; in the UK it’s 1.5 µg per day; and in the EU it’s 1 µg per day.

On average the guideline is about 2 µg (micrograms) per day for adults and <1 µg per day for children.

One microgram is one-millionth of a gram, so only trace amounts of this vitamin are required.

What happens if you don’t consume enough vitamin B12?

Symptoms of vitamin B12 deficiency include a type of anaemia, called megaloblastic or macrocystic anaemia, which results from inhibition of DNA synthesis during production of red blood cells. The red blood cells grow larger than normal and are less able to carry oxygen.

B12 deficiency anaemia

Megaloblastic anaemia is fatal if untreated, but can usually be reversed with B12 injections and sometimes with B12 tablets (2).

Anaemia caused by a lack of vitamin B12 can result in symptoms which include:
• Extreme tiredness or fatigue
• A lack of energy or lethargy
• Being out of breath
• Feeling faint
• Headache
• Ringing in the ears (tinnitus)
• Lack of appetite

More specific symptoms linked to a lack of vitamin B12 include:
• Yellowing of the skin
• Sore, red tongue
• Mouth ulcers
• Changes or loss of some sense of touch
• Feeling less pain
• Walking problems
• Vision problems
• Mood changes, irritability, depression or psychosis
• Symptoms of dementia

Rarely, vitamin B12 deficiency can result in irreversible damage to the nervous system.

Over the last decade or so, researchers have strongly implicated the toxic amino acid homocysteine in a variety of disease states.

Homocysteine tends to accumulate in the body whenever vitamin B12 gets deficient, and this accumulation has been linked with increased risk of Alzheimer’s and other neuropsychiatric disease (3-5), cardiovascular disease (6,7) chronic fatigue syndrome and fibromyalgia (8) multiple sclerosis (9) and kidney disease (10), among other conditions.

Folic acid deficiency can also lead to increased homocysteine levels. This is because folate and vitamin B12, in their active ‘coenzyme’ forms, are both necessary cofactors for the enzymatic conversion of homocysteine to methionine.

Until recently it was thought that the availability of folate was the most important determinant of the body’s ability to re-methylate homocysteine.

New research has revealed that vitamin B12 is more important for homocysteine disposal than previously believed (9,11-13).

For example, a study conducted among dialysis patients with kidney failure showed that a monthly injection of vitamin B12 plus conventional oral folate was more effective than high-dose folate without vitamin B12 in lowering elevated homocysteine (11).

Where does vitamin B12 come from?

Vitamin B12 is synthesised only by certain bacteria, and is not made by either plants or animals.

Ruminants, like cows, goats, sheep, giraffes, llamas, buffalo, and deer, are unique in that bacteria in their stomachs (rumen) synthesise vitamin B12, which then moves down and is absorbed by their small intestines.


Animal tissues store bacteria-synthesised vitamin B12, which can then be passed along the food chain by animals eating other animals (14).

The human gut also contains vitamin B12-synthesising bacteria, living from the mouth to the anus (15).

In humans, most intestinal vitamin B12 is produced in our large intestine, or colon, which is home to 4 trillion bacteria per cm3 of faeces.

Unfortunately, most vitamin B12 is absorbed in the small intestine, which is upstream of the large intestine, so the B12 produced in the latter is largely unavailable to us, unless we eat poop, which is obviously not recommended.

Faeces of cows, chickens and sheep also contain active vitamin B12.

In the past, people lived in close contact with farm animals. Animal manure was used to fertilise the land and people ate vegetables straight from the soil, so they would naturally have consumed small amounts of vitamin B12, even if they did not eat animal products.

Traditional agriculture

Nowadays, most people have little or no contact with farm animals and consume vegetables which are industrially washed and disinfected before reaching supermarkets. In addition, our living environments are heavily sanitised.

These changes to human lifestyle, whilst beneficial in many respects, have likely led to a reduction in naturally occurring intake of vitamin B12.

Though it’s generally stated that people don’t benefit much from the synthesis of vitamin B12 in the human gut because most is made in the colon, there is evidence from healthy subjects that at least two groups of organisms in the small intestine, Pseudomonas and Klebsiella sp., may synthesise significant amounts of vitamin B12 which can be actively absorbed in the presence of intrinsic factor (16).

Foods derived from animals – meat, milk, eggs, fish and shellfish – are thus the major dietary sources of vitamin B12; the richest natural sources are liver and kidney.

Vitamin B12 content of food

Animal-derived sources of vitamin B12

Eating a diet rich in animal products will, however, give you a one-in-two chance of dying prematurely from a heart attack or stroke; a one-in-seven chance of breast cancer or a one-in-six chance of prostate cancer (17). Such a diet also results in obesity, diabetes, osteoporosis, constipation, indigestion, and arthritis (18).

So what can you do to avoid vitamin B12 deficiency if you don’t want to eat animals?

Vitamin B12 deficiency and plant-based diets

If you’re on a strict vegan diet – no meat, fish, dairy, or eggs – you have a low risk of vitamin B12 deficiency, which increases gradually with time, as body reserves of B12 are used up.

On average, for someone raised on the Western diet, about 2 to 5 milligrams of B12 are stored, mostly in the liver. It’s been calculated that most people have a 3 to 6 year reserve of this vital nutrient (19).

Conservation of B12 by the body boosts the time this supply lasts by 10-fold.

It’s estimated to take at least 20-30 years to deplete body reserves of vitamin B12, in the unlikely event of zero vitamin B12 intake during this period, as there are efficient mechanisms for re-absorbing and re-circulating B12 between the liver and intestines (20).

Vitamin B12 deficiency is more common in older people and affects around one in 10 over 75s (21).

Elderly people

Pregnant women on a strict vegan diet are also at a higher risk of B12 deficiency (22).

Blood levels of vitamin B12 can be measured directly and are a means to help diagnose deficiency.

Values above 150 pg/ml (picograms per millilitre) are considered normal, and levels below 80 pg/ml represent unequivocal B12 deficiency (23).

Absorption of vitamin B12

Vitamin B12 deficiency most commonly occurs due to health problems with the stomach and intestine, caused by autoimmune diseases, ulcers, parasites or surgery, rather than to a lack of B12 in the diet (24).

Vitamin B12 is the only nutrient that requires a cofactor for efficient absorption.

The cells of the stomach produce a substance, called intrinsic factor, which combines with vitamin B12 released from food, after acidic digestion in the stomach (25).

small intestine, colon

This intrinsic factor-B12 complex then travels to the end of the small intestine, called the ileum, where it’s actively absorbed.

If intrinsic factor isn’t produced due to damage to the parietal cells of the stomach, for example caused by pernicious anaemia, vitamin B12 cannot be absorbed and does not reach the cells where it’s needed.

Vitamin B12 can cross the intestine by passive absorption, but this mechanism does not use intrinsic factor; as a result, it’s 1000 times less efficient (26).

Plant-based sources of vitamin B12

As highlighted above, vitamin B12 is made only by certain bacteria and not by plants or animals.

Some plant-based foods have been shown to contain vitamin B12, due to their association with bacteria that synthesise it.

I’ve already mentioned that different forms of vitamin B12 exist, some of which are biologically inactive and are referred to as pseudovitamin B12.

When reviewing the scientific literature, it’s important to be clear if a food source contains active or inactive vitamin B12, as well as how reliable it is as a source of vitamin B12.

Consuming inactive or pseudovitamin B12 will not benefit your health in the slightest.

Growing vegetables in organic cow manure

Some reports in the literature suggest that adding an organic fertiliser such as cow manure significantly increases the vitamin B12 content of vegetables such as spinach leaves, i.e., approximately 0.14 μg per 100 g fresh weight (27).

organic vegetables

This sounds potentially exciting but research indicates that most organic fertilisers, particularly those made from animal manures, contain considerable amounts of the inactive form – pseudovitamin B12 (28).

It’s also worth pointing out that you’d have to eat 3 lb (1.4 kg) of this organically grown spinach to obtain the guideline daily amount of vitamin B12.


A fermented soybean-based food called tempeh has been shown to contain a considerable amount of biologically active vitamin B12 (0.7–8.0 μg per 100 g) (29).

Tempeh originated in Indonesia and is made from whole soybeans, which are soaked, de-hulled, and partly cooked. They are then fermented for 24 to 36 hours at 30°C with the spores of a fungus, Rhizopus oligosporus or Rhizopus oryzae, forming a solid block meshed together with a white mycelium.

Soy products

Different batches of tempeh may vary substantially in the amount of vitamin B12 they contain, so this is not necessarily a reliable source.

Cooked tempeh can be eaten alone, or used in chilli, stir fries, soups, salads, sandwiches, and stews. Tempeh’s complex flavour has been described as nutty, meaty, and mushroom-like. It freezes well, and is now commonly available in many western supermarkets, as well as in ethnic markets and health food stores.

Tea leaves

Vitamin B12 is also found in various types of tea leaves (approximately 0.1 to 1.2 μg vitamin B12 per 100 g dry weight) (30).

For example, vitamin B12-deficient rats were fed a Japanese fermented black tea (Batabata-cha) drink for 6 weeks, and their B12 deficiency was reduced compared with control rats (31).

Consumption of 1–2 litres of the fermented tea drink (typical regular consumption in Japan), which is equivalent to 20 to 40 ng of vitamin B12, is not however sufficient to meet the guideline daily intake of 2 μg per day for adult humans.

japanese tea ceremony

It’s important to note that Japanese teas such as Batabata-cha are made in a different way from the Indian black teas commonly consumed in Europe and the US, so the results are not applicable to tea-drinking in general.

You can buy Batabata-cha online.


Mushrooms are fungi rather than plants. Various species of mushroom have been analysed for active vitamin B12 content.

Several wild edible mushroom species popular in Europe were found to contain zero or trace levels (approximately 0.09 μg per 100 g dry weight) of vitamin B12: porcini mushrooms (Boletus sp.), parasol mushrooms (Macrolepiota procera), oyster mushrooms (Pleurotus ostreatus), and black morels (Morchella conica).

In contrast, the fruiting bodies of black trumpet (Craterellus cornucopioides) and golden chanterelle (Cantharellus cibarius) contained higher levels of active vitamin B12 (1.09–2.65 μg per 100 g dry weight) (32).

High levels of active vitamin B12 were detected in the commercially available dried shiitake mushroom fruiting bodies (Lentinula edodes), with the average measured at approximately 5.61 μg per 100g dry weight (33).

mushrooms containing vitamin B12

Shiitake mushrooms

Shiitake mushrooms can be added to soups and stir-fries, steamed, or sautéed with onions and other vegetables to create a wide variety of nutritious and delicious dishes.

Please click here for a recipe for mushroom stroganoff – a plant-based, vegan recipe using shiitake mushrooms and nutritional yeast, which contains 112 per cent of the recommended daily intake of vitamin B12 per serving.

Vegan, plant-based recipe for mushroom stroganoff

Mushroom Strogonoff

Sea vegetables (seaweed)

Nori – the dried green and purple lavers commonly used to make sushi (Enteromorpha sp. and Porphyra sp., respectively) – contain substantial amounts of the biologically active form of vitamin B12 (approximately 63.6 μg per 100 g dry weight and 32.3 μg per 100 g dry weight, respectively) (34).

Please click here for a recipe for vegetable sushi nori.

How to make vegetable sushi rolls

Vegetable sushi nori

A nutritional analysis of six vegan children who had consumed vegan diets including brown rice and dried purple laver (nori) for 4 to 10 years suggested that the regular consumption of nori may prevent vitamin B12 deficiency (35).

Other edible seaweeds contain zero or only trace levels of vitamin B12.

Foods fortified with vitamin B12

Vitamin B12 can be obtained from many everyday food items that are fortified, such as veggie burger and sausage mixes, yeast extracts, vegetables stocks, margarines, breakfast cereals and soya milks.

Many of these food products are heavily processed, so please read the labels to check what you’re consuming.

See the table below for a guide to how much vitamin B12 is contained in a range of these foods.

foods fortified with B12

Sources: McCance and Widdowson (36) and manufacturers’ product information


Vitamin B12 supplements

Vitamin B12 is found in almost all multivitamins, often referred to by its scientific name, cobalamin.

Dietary supplements that contain only vitamin B12, or vitamin B12 with nutrients such as folic acid and other B vitamins, are also available.


Vitamin B12 is also available in sublingual forms (which are dissolved under the tongue). There is no evidence that sublingual forms are better absorbed than pills that are swallowed.

A prescription form of vitamin B12 can be administered as an injection. This is usually used to treat vitamin B12 deficiency.

Vitamin B12 is also available as a prescription medication in nasal gel form (for use in the nose).

Forms of vitamin B12 in supplements

As a food additive and a supplement pill, vitamin B12 is usually found in the form cyanocobalamin, which is cobalamin bonded to a cyanide ligand.

Cyanocobalamin does not occur in nature, but is produced semi-synthetically from bacterial hydroxycobalamin and then used in many pharmaceuticals and supplements, and as a food additive, because of its stability and lower production cost.

Cyanocobalamin was originally produced by accident and at first remained unrecognised.

Historically, during the production process, activated charcoal columns were used to purify vitamin B12 synthesised by bacteria.

Cyanide is naturally present in activated charcoal, and hydroxycobalamin, which has great affinity for cyanide, picks it up, and is changed to cyanocobalamin.

Nowadays, industrial production of cyanocobalamin begins with fermentation of the bacteria Propionibacterium shermanii or Pseudomonas denitrificans; these strains make about 100 000 times more vitamin B12 than they need for their own growth (37,38).

This process yields a mixture of methyl-, hydroxy-, and adenosylcobalamin.

These compounds are converted to cyanocobalamin by addition of potassium cyanide in the presence of sodium nitrite and heat.

In the body, cyanocobalamin is converted to the human physiological forms methylcobalamin and adenosylcobalamin, leaving behind the cyanide, albeit in minimal concentration.

Is cyanocobalamin toxic?

On many natural health sites on the internet, you’ll come across warnings about the alleged toxicity of cyanocobalamin due to the production of cyanide during its metabolism.

Is this fact or fiction?

Cyanides can occur naturally or be man-made and it’s true that many are powerful and rapid-acting poisons.

Hydrogen cyanide (HCN), which is a gas, and the simple cyanide salts (sodium cyanide and potassium cyanide) are common examples of cyanide compounds.

Certain bacteria, fungi, and algae can produce cyanide, and cyanide is found naturally in a number of foods and in over 2650 plants (39-41).

In certain plant foods, including almonds, millet sprouts, lima beans, soy, spinach, bamboo shoots, and cassava roots (which are a major source of food in tropical countries), cyanides occur naturally as part of sugars and other compounds. The sugar-cyanide complexes are sometimes referred to as cyanogenic glycosides.

cyanogenic glycosides in food

Cyanide in food plants (39-41)

When the plant is damaged or chewed a chemical reaction occurs in the harmed cell and the cyanide is released as a natural defence.

The human body can detoxify a small amount of cyanide in the liver through a pathway involving a molecule called thiosulfate.

Researchers have estimated the rate of detoxification of cyanide in humans at between 1µg (micrograms) and 17µg per kg per minute in the absence of antidotes (42).

Poisoning occurs when there is not enough thiosulfate to neutralise all the cyanide.

At low toxic concentrations cyanide can provoke nausea, vomiting, general weakness and dizziness.

At lethal concentrations, cyanide inhibits cellular respiration, causing cardiac arrest and rapid death.

A lethal dose to humans is thought to be 98 mg (milligrams) in one day, with a lowest documented lethal dose of 37.8 mg (0.54mg/kg body weight) (43).

The amount of cyanide in 1000 µg (1000 micrograms or 1 milligram) of cyanocobalamin is 20 µg (micrograms), or 0.05 per cent of the lower level thought to be harmful.

To put this in context, the inhaled smoke from one cigarette contains 40 to 100 µg cyanide (44).

Plants contain between 0.01 to 5 µg hydrogen cyanide (HCN) per 1000 µg (mg) (39-41).

So if you ate, say, I tablespoon (10 g) of flax meal, you’d potentially consume 3600 µg HCN, which is obviously much more than the 2 µg cyanide from eating a 1000 µg cyanocobalmin pill.

cyanogenic glycosides

Food plants containing cyanide


The safety and effectiveness of the cyanocobalamin “cyanide complex” for treating neurologic problems has, however, been questioned; therefore, other forms, such as methylcobalamin and hydroxycobalamin are also used for the prevention and treatment of B12-related conditions (45).

Hydroxycobalamin is typically used in vitamin B12 injections but is reported to be less stable than cyanocobalamin.

Chemical stability studies show that, at worst, a solution of hydroxycobalamin in pH 4.3 acetate buffer will retain at least 90 per cent of claimed cobalamin at 30°C for 170 weeks (46).

If you’d prefer to avoid consuming even small amounts of cyanide every day, you can also buy liquid supplements for oral use containing hydroxycobalamin.

Existing evidence does not suggest any substantial differences among forms with respect to absorption or bioavailability.

Are ‘natural’ vitamin B12 supplements better?

High levels of vitamin B12 are described on the nutritional labels of dietary supplements that contain edible blue-green algae (cyanobacteria) such as Spirulina, Aphanizomenon, and Nostoc.

Although substantial amounts of vitamin B12 are detected in these commercially available supplements, lab studies show that these supplements often contain large amounts of pseudovitamin B12, which has no biological effect (47).

chlorella supplements

Chlorella tablets (eukaryotic microalgae Chlorella sp.) used in human food supplements contain biologically active vitamin B12 (48), however, contents vary substantially between commercially available Chlorella tablets (from zero to several hundred μg of vitamin B12 per 100 g dry weight), so these may be an unreliable source (33).

Can vitamin B12 supplements interact with medicines?

Vitamin B12 can interact or interfere with medicines that you take, and in some cases, medicines can lower vitamin B12 levels in the body.

Here are several examples of medicines that can interfere with the body’s absorption or use of vitamin B12:
• Chloramphenicol (Chloromycetin®), an antibiotic that is used to treat certain infections.
• Proton pump inhibitors, such as omeprazole (Prilosec®) and lansoprazole (Prevacid®), that are used to treat acid reflux and peptic ulcer disease.
• Histamine H2 receptor antagonists, such as cimetidine (Tagamet®), famotidine (Pepcid®), and ranitidine (Zantac®), that are used to treat peptic ulcer disease.
• Metformin, a drug used to treat diabetes.

You are advised to tell your doctor, pharmacist, and other health care providers about any dietary supplements and medicines you take. They can tell you if those dietary supplements might interact or interfere with your prescription or over-the-counter medicines or if the medicines might interfere with how your body absorbs, uses, or breaks down nutrients.

What dose of vitamin B12 supplement should I take?

As noted above, official dietary guidelines for intake of vitamin B12 are approximately 2 µg (micrograms) per day for adults and less than 1 µg per day for children.

Most vitamin B12 supplements sold contain 500 to 5000 µg (micrograms) per pill, which is between 250 and 2500 fold higher than the guideline dietary intake.

The body’s ability to absorb vitamin B12 from dietary supplements is largely limited by the capacity of intrinsic factor produced in the stomach.

Studies have shown that absorption of physiological doses of vitamin B12 is limited to approximately 1.5 to 2 µg per dose or meal, due to saturation of the active uptake system (49).

Regardless of dose, approximately 1 per cent of vitamin B12 is absorbed by passive diffusion and consequently this process becomes quantitatively important at high levels of exposure (50,51).

Bioavailability for those who need vitamin B12 the most is especially poor, because of weaknesses in their stomach and intestines, affecting either classical intrinsic factor-mediated absorption or passive B12 absorption.

In healthy subjects, bioavailability of cyanocobalamin has been shown to be approximately 5 per cent of the oral dose (52).

Evidence shows that many elderly persons respond poorly to daily oral doses under 500 µg, with bioavailability of 2 per cent or less (53,54).

Those least in need of vitamin B12 usually have normal absorption and are thus at greatest risk for whatever unknown adverse effects of high-dose supplementation or fortification might emerge, such as potential effects of excess accumulation of cyanocobalamin (55).

That said, in 2000 the European Union Scientific Committee on Food concluded that no adverse effects have been associated with excess vitamin B12 intake from food or supplements in healthy individuals, and that vitamin B12 has a history of safe long-term use as a therapeutic agent given in high dosages (56).

In vitamin B12 replacement therapy oral dosages between 1-5 mg (milligrams) vitamin B12 are used, with no supportive evidence of adverse effects (56).


From reviewing the literature, it appears that elderly people suffering from vitamin B12 deficiency are either given injections of 1000 µg once per day for 10 days (after 10 days, the dose is changed to once weekly for four weeks, followed by once monthly for life); or oral doses of 125 to 2,000 micrograms daily for up to 2.5 years or longer, to ensure adequate amounts are reaching the bloodstream.

Otherwise healthy meat or fish eaters are unlikely to need supplements at all.

For healthy people on strict vegan or plant-based diets, who are not consuming fortified foods or foods naturally containing vitamin B12, one 500 µg pill per week or 5µg of a liquid formulation per day is likely to be adequate (57).

If you’re concerned about your vitamin B12 levels, please go and consult your physician or qualified healthcare provider. They’ll be able to arrange for blood tests to check:

  • whether you have a lower level of haemoglobin (a substance that transports oxygen) than normal
  • whether your red blood cells are larger than normal
  • the level of vitamin B12 in your blood
  • the level of folate in your blood

These tests can often help identify people with a possible vitamin B12 or folate deficiency, but they are not necessarily conclusive, because some people can have problems with normal levels of these vitamins, and others can have low levels despite having no symptoms.

This means it is very difficult to devise definitive criteria for the diagnosis of vitamin B12 or folate deficiency, and this is why it is important for your symptoms to be taken into account when a diagnosis is made.

I hope this post has helped to answer any questions you may have had about vitamin B12 – if you have any others, please write in the comments below.

dividing line

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1. Krautler B. Vitamin B12: chemistry and biochemistry. Biochemical Society transactions. 2005;33(Pt 4):806-810.
2. Butler CC, Vidal-Alaball J, Cannings-John R, et al. Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency: a systematic review of randomized controlled trials. Family Practice. 2006;23(3):279-285.
3. McCaddon A DG, Hudson P, Tandy S, Cattell H. . Total serum homocysteine in senile dementia of Alzheimer type. Int J Geriatr Psychiatry. 1998;13(4):235-239.
4. Clarke R SA, Jobst KA, Refsum H, Sutton L, Ueland PM. . Folate, vitamin B12, and serum total homocysteine levels in confirmed Alzheimer disease. Arch Neurol. 1998;55(11):1449-1455.
5. Stanger O, Fowler B, Piertzik K, et al. Homocysteine, folate and vitamin B12 in neuropsychiatric diseases: review and treatment recommendations. Expert review of neurotherapeutics. 2009;9(9):1393-1412.
6. Araki A SY, Ito H. . Plasma homocysteine concentrations in Japanese patients with non-insulin-dependent diabetes mellitus: effect of parenteral methylcobalamin treatment. Atherosclerosis. 1993;103(2):149-157.
7. Wald DS, Law M, Morris JK. Homocysteine and cardiovascular disease: evidence on causality from a meta-analysis. Vol 3252002.
8. Regland B AM, Abrahamsson L, Bagby J, Dyrehag LE, Gottfries CG. . Increased concentrations of homocysteine in the cerebrospinal fluid in patients with fibromyalgia and chronic fatigue syndrome. Scand J Rheumatol. 1997;26(4):301-307.
9. Baig SM QG. Homocysteine and vitamin B12 in multiple sclerosis. Biogenic Amines. 1995;11(6):479-485.
10. Levi A, Cohen E, Levi M, Goldberg E, Garty M, Krause I. Elevated serum homocysteine is a predictor of accelerated decline in renal function and chronic kidney disease: A historical prospective study. European journal of internal medicine. 2014;25(10):951-955.
11. Hoffer LJ BI, Hongsprabhas P, Shrier I, Saboohi F, Davidman M, Bercovitch DD, Barre PE. A tale of two homocysteines–and two hemodialysis units. Metabolism. 2000;49(2):215-219.
12. D’Angelo A CA, Madonna P, Fermo I, Pagano A, Mazzola G, Galli L, Cerbone AM. The role of vitamin B12 in fasting hyperhomocysteinemia and its interaction with the homozygous C677T mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. A case-control study of patients with early-onset thrombotic events. 2000;83(4):563-570.
13. Yajnik CS, Lubree HG, Thuse NV, et al. Oral vitamin B12 supplementation reduces plasma total homocysteine concentration in women in India. Asia Pacific journal of clinical nutrition. 2007;16(1):103-109.
14. Watanabe F YY, Tanioka Y, Bito T. Biologically active vitamin B12 compounds in foods for preventing deficiency among vegetarians and elderly subjects. J Agric Food Chem. . 2013;61(28)(Jul 17):6769-6775.
15. Albert MJ MV, Baker SJ. . Vitamin B12 synthesis by human small intestinal bacteria. Nature. 1980;283(5749)(Feb 21):781-782.
16. Albert MJ, Mathan VI, Baker SJ. Vitamin B12 synthesis by human small intestinal bacteria. Nature. 1980;283(5749):781-782.
17. Campbell TC, Campbell TM. The China study : the most comprehensive study of nutrition ever conducted and the startling implications for diet, weight loss and long-term health. 1st BenBella Books ed. Dallas, Tex.: BenBella Books; 2005.
18. McDougall J. The Starch Solution. Rodale Press; 2013.
19. Institute of Medicine (US) Standing Committee on the Scientific Evaluation of Dietary Reference Intakes and its Panel on Folate OBV, and Choline. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Estimation of the Period Covered by Vitamin B12 Stores. Washington (DC): National Academies Press (US);1998.
20. Schjonsby H. Gut. 1989;30:1686-1691.
21. Control CfDPa. Vitamin B12 Deficiency.
22. Black MM. Effects of vitamin B(12) and folate deficiency on brain development in children. Food and nutrition bulletin. 2008;29(2 Suppl):S126-131.
23. Stabler S AR. Vitamin B12 Deficiency As A Worldwide Problem. Annu. Rev. Nutr. 2004;24:299-326.
24. Stabler SP. Vitamin B12 Deficiency. New England Journal of Medicine. 2013;368(2):149-160.
25. Kozyraki R, Cases O. Vitamin B12 absorption: mammalian physiology and acquired and inherited disorders. Biochimie. 2013;95(5):1002-1007.
26. ARMSTRONG BK. Absorption of Vitamin B12 from the Human Colon. The American journal of clinical nutrition. 1968;21(4):298-299.
27. A. M. Enrichment of some B-vitamins in plants with application of organic fertilizers. Plant Soil. 1994;167:305-311.
28. Bito T. ON, Takenaka S., Yabuta Y., Miyamoto E., Nishihara E., Watanabe F. . Characterization of vitamin B12 compounds in biofertilizers containing purple photosynthetic bacteria. Trends Chromatogr. 2012;7:23-28.
29. Nout M.J.R. RFM. Recent developments in tempe research. J. Appl. Bacteriol. 1990;69:609-633.
30. Kittaka-Katsura H WF, Nakano Y. Occurrence of vitamin B12 in green, blue, red, and black tea leaves. J Nutr Sci Vitaminol (Tokyo). 2004;50 (6)(Dec):438-440.
31. Kittaka-Katsura H. ES, Watanabe F., Nakano Y. . Characterization of corrinoid compounds from a Japanese black tea (Batabata-cha) fermented by bacteria. J. Agric. Food Chem. 2004;52:909-911.
32. Watanabe F. SJ, Takenaka S., Miyamoto E., Ohishi N., Nelle E., Hochstrasser R., Yabuta Y. . Characterization of vitamin B12 compounds in the wild edible mushrooms black trumpet (Craterellus cornucopioides) and golden chanterelle (Cantharellus cibarius). J. Nutr. Sci. Vitaminol. 2012;58:438-441.
33. Watanabe F, Yabuta, Y., Bito, T., & Teng, F. Vitamin B12-Containing Plant Food Sources for Vegetarians. Nutrients. 2014;6(5):1861–1873.
34. Watanabe F. TS, Katsura H., Masumder S.A., Abe K., Tamura Y., Nakano Y. Dried green and purple lavers (nori) contain substantial amounts of biologically active vitamin B12 but less of dietary iodine relative to other edible seaweeds. J. Agric. Food Chem. 1999;47:2341–2343.
35. H S. Serum vitamin B12 levels in young vegans who eat brown rice. J Nutr Sci Vitaminol (Tokyo). 1995;41(6):587-594.
36. Agency FS. McCance and Widdowsons the Composition of Food. 7th ed. London: Royal Society of Chemistry; 2014.
37. Spalla C GA, Garofano L, Ferni G. . Microbial production of vitamin B12. In: EJ V, ed. Biotechnology of vitamins, pigments and growth factors. New York: Elsevier Appl Science; 1989:257-284.
38. Kusel JP FY, Demain AL. . Betaine stimulation of vitamin B12 biosynthesis in Pseudomonas denitrificans may be mediated by an increase in activity of d-aminolaevulinic acid synthase. J Gen Microbiol. 1984;130:835-841.
39. Haque MR BJ. Total cyanide determination of plants and foods using the picrate and acid hydrolysis methods. Food chemistry. 2002;77(1):107-114.
40. Simeonova FP FL. Hydrogen cyanide and cyanides: Human health aspects. Geneva: World Health Organisation;2004.
41. Shragg TA AT, Fisher Jr CJ. Cyanide poisoning after bitter almond ingestion. Western Journal of Medicine. 1982;136(1):65-69.
42. Newhouse KaC, N. Toxicological review of hydrogen cyanide and cyanide salts. Washington DC: US Environmental Protection Agency;September 2010.
43. Safety) IIPoC. Hydrogen cyanide and cyanides: human health aspects. Geneva: World Health Organization;2004.
44. Fiskel J CC, and Eschenroeder A. . Exposure and risk assessment for cyanide. 1981.
45. AG. F. Hydroxocobalamin versus cyanocobalamin. J R Soc Med. 1996;89(11)(Nov):659.
46. Marcus AD, Stanley JL. Stability of the cobalamin moiety in buffered aqueous solutions of hydroxocobalamin. Journal of Pharmaceutical Sciences. 1964;53(1):91-94.
47. Watanabe F KH, Takenaka S, Fujita T, Abe K, Tamura Y, Nakatsuka T, Nakano Y. Pseudovitamin B(12) is the predominant cobamide of an algal health food, spirulina tablets. J Agric Food Chem. 1999;47(11):4736-4741.
48. Kittaka-Katsura H. FT, Watanabe F., Nakano Y. . Purification and characterization of a corrinoid-compound from chlorella tablets as an algal health food. J. Agric. Food Chem. 2002;50:4994–4997.
49. Minerals EGoVa. Report on safe upper levels for vitamins and minerals. LondonMay 2003.
50. Scott JM. Bioavailability of vitamin B12. European journal of clinical nutrition. 1997;51 (Suppl. 1):S49-S53.
51. Baik HWaR, R.M. Vitamin B12 deficiency in the elderly. Annual Review Nutrition. 1999;19:357-377.
52. Castelli MC, Wong DF, Friedman K, Riley MGI. Pharmacokinetics of Oral Cyanocobalamin Formulated With Sodium N-[8-(2-hydroxybenzoyl)amino]caprylate (SNAC): An Open-Label, Randomized, Single-Dose, Parallel-Group Study in Healthy Male Subjects. Clinical Therapeutics.33(7):934-945.
53. Eussen SJ dGL, Clarke R, et al. . Oral cyanocobalamin supplementation in older people with vitamin B12 deficiency: a dose-finding trial. Arch Intern Med. 2005;165(10)(May 23):1167-1172.
54. Hill MH, Flatley JE, Barker ME, et al. A vitamin B-12 supplement of 500 mug/d for eight weeks does not normalize urinary methylmalonic acid or other biomarkers of vitamin B-12 status in elderly people with moderately poor vitamin B-12 status. The Journal of nutrition. 2013;143(2):142-147.
55. Carmel R. Efficacy and safety of fortification and supplementation with vitamin B12: biochemical and physiological effects. Food and nutrition bulletin. 2008;29(2 Suppl):S177-187.
56. 2000. SCoFSCoFNEoO. Opinion of the Scientific Committee on Food on the tolerable upper intake level of vitamin B12. 2000.
57. McDougall J. Vitamin B12 Deficiency—the Meat-eaters’ Last Stand. McDougall Newsletter. November 2007.


On celery, seduction, science and salad

Recently, I posted a little poem by Ogden Nash on my Facebook page.

celery by ogden nash

Seeing this, one of my friends asked me about the health benefits of celery and whether it makes any difference if you eat it raw or cooked.

So here are some answers to these questions.

But first some celery background and a story of seduction.

Botany and history

Celery (Apium graveolens L.) is a member of the same botanical family as carrots, parsley and fennel – the Umbelliferae.

celery botanical drawing

Celery is a member of the Umbelliferae

Modern celery originated from wild celery, native to the Mediterranean, where its seeds were once widely used as a medicine (1).  It was not cultivated as a food plant until 1623.

Wild celery was mentioned in Homer’s Odyssey in about 850 BCE (2).

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Odysseus and his companions were on their way to their beloved Ithaca, but Poseidon, the moody god of the seas, became angry with the hero. So he sank all the ships of Odysseus and drowned his companions.

Shipwrecked, Odysseus was tortured for nine days and nights, until the waves took him to a beautiful island called Ogygia, believed to be in Western Europe.

There he was seduced by a nymph called Calypso, who fell in love with him and would not allow him to leave.

Jan Brueghel-Calypso's Cave

Calypso’s Cave by Jan Brueghel

Eventually, after seven years, Zeus – King of the gods – sent his messenger Hermes to tell Calypso to let Odysseus go.

So Hermes travelled over the endless breakers, until he reached the distant isle, then leaving the violet sea he crossed the land, and came to the vast cave where the nymph of the lovely tresses lived, and found her at home.

A great fire blazed on the hearth, and the scent of burning cedar logs and juniper spread far across the isle. Sweet-voiced Calypso was singing within, moving to and fro at her loom, weaving with a golden shuttle. Around the cave grew a thick copse of alder, poplar and fragrant cypress, where large birds nested, owls, and falcons, and long-necked cormorants whose business is with the sea. And heavy with clustered grapes a mature cultivated vine went trailing across the hollow entrance. And four neighbouring springs, channelled this way and that, flowed with crystal water, and all around in soft meadows iris and wild celery flourished.

Celery was considered an aphrodisiac by the Ancient Greeks and Romans (3).

Some have speculated that Calypso was rendered ravenous by her celery-rich diet and pounced on Odysseus, detaining him for years of amorous activity.

Is there any scientific evidence to support the use of celery as an aphrodisiac?

More on that later.

There is however no doubt that, for whatever reason, celery was highly prized in ancient times and its leaves were used as garlands for the winners at the Isthmian and Nemean games.

In both Ancient Greece and Ancient Egypt, celery leaves were also used as garlands for the dead. Dried inflorescences and leaves of celery were reportedly found in the tomb of Tutankhamun (4).

But back to the story…

Calypso was not best pleased when Hermes explained his mission. She ranted and raved and accused him of jealousy.

Realising, however, that it was futile to argue with Zeus, Calypso sorrowfully followed the order.

She gave Odysseus enough tools to build a solid raft.

Odysseus loaded the raft with plenty of water and food and finally made his farewells to embark on a world of new adventures.

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Health benefits of celery

So what can celery do for you?

My friend said he thought celery was a pointless food – nothing but water, which takes more energy to digest than it provides.

How true is this perception?

Nutritional content of celery

Well it is true that celery contains a lot of water – 95 per cent water to be precise.

Celery is also, however, rich in vitamin C and fibre. It is a very good source of potassium, folic acid and vitamins B6 and B1; and a good source of calcium and vitamin B2 (5).

Whilst celery does contain more sodium than other vegetables, this is offset by very high levels of potassium.

One 8-inch (20 cm) celery stalk contains approximately 32 milligrams of sodium and 104 milligrams of potassium, whilst providing only 6 calories as carbohydrate (5).

This reminds me to address one common question about celery.

Celery stalks

Is it true that you burn more calories eating celery than it provides?

A search of the internet uncovers all manner of speculation on this subject but very little scientific evidence to support it.

What we do know from science is that approximately 10 per cent of the calories we consume each day are used up in the process of eating and digesting food.

This energy ‘waste’ is called the thermogenic effect of food, dietary-induced thermogenesis, the ‘specific heat of feeding’, or the thermic effect of food.

All this means is that every time we eat, some of the calories contained in the food are lost as heat.

The exact amount of heat lost during eating can be measured by putting someone in a whole body calorimeter, giving them food to eat, and recording the change in temperature.

To my knowledge, nobody has actually measured a person’s heat production after eating a meal of celery alone, so we are left to guess what might happen from the results of other experiments.

Measurements show that some foods are digested with little heat loss, for example, fat-based foods.

High protein foods are the opposite and generate a lot of heat – presumably because the body has to work harder to digest protein.

Celery consists of mostly water and fibre. So what is the thermogenic effect of water and fibre?

Almost nothing.

In fact, if you put someone in a whole body calorimeter and give them a high-fibre diet, their post-food heat production is actually reduced compared to a normal diet (6)(7)(8).

Supplementing a balanced 240 kcal meal with 3 grams of fibre (equivalent of five celery stalks) reduces the overall thermogenic effect of the meal by 19 kcal. This effectively means that of the 30 calories gained from eating your celery stalks, 19 calories fewer are used processing it than if it did not have the fibre in it.

So, after being chewed, the fibre in celery gets passed through the gut and out the other end without the body doing too much to it on the way. Although it may take you a while to chew the celery stalks, the gut does not waste much time on it.

So, sorry dieters, but it is unlikely that eating celery burns more calories than it provides.

You could go for a walk whilst munching celery; that would work.

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For those of you who like geeky information, here is a detailed breakdown of the nutrients in raw celery.

Nutrient Unit   Value per 100 g
Water g 95.43
Energy kcal 16
Protein g 0.69
Total lipid (fat) g 0.17
Carbohydrate, by difference g 2.97
Fibre, total dietary g 1.6
Sugars, total g 1.83
Calcium, Ca mg 40
Iron, Fe mg 0.2
Magnesium, Mg mg 11
Phosphorus, P mg 24
Potassium, K mg 260
Sodium, Na mg 80
Zinc, Zn mg 0.13
Vitamin C, total ascorbic acid mg 3.1
Thiamin mg 0.021
Riboflavin mg 0.057
Niacin mg 0.32
Vitamin B-6 mg 0.074
Folate, DFE µg 36
Vitamin B-12 µg 0
Vitamin A, RAE µg 22
Vitamin A, IU IU 449
Vitamin E (alpha-tocopherol) mg 0.27
Vitamin D (D2 + D3) µg 0
Vitamin D IU 0
Vitamin K (phylloquinone) µg 29.3
Fatty acids, total saturated g 0.042
Fatty acids, total monounsaturated g 0.032
Fatty acids, total polyunsaturated g 0.079
Cholesterol mg 0

Phytochemical content

In addition to the nutrients listed above, celery contains literally hundreds of powerful phytochemicals (9).

Celery seeds contain 1.5 to 3 per cent volatile oil responsible for the characteristic aroma of celery.  The chemical constituent of celery seed volatile oil was found to be 60–70 per cent limonene, phthalides and β-salinene, coumarins, furanocoumarins (bergapten) and flavonoids (apiin, apigenin).

Some of the phytochemicals identified in celery are listed below (10).

n-butyl phthalide
Cinnamic aldehyde
Geranyl acetate
Pentyl benzene
(Cis) beta-Ocimene

Use as a herbal medicine

Traditionally, wild celery was used as an herbal medicine with a range of alleged properties (11) (12), including:

  • Aphrodisiac
  • Anthelmintic
  • Anti-inflammatory, for rheumatic conditions
  • Antiseptic, especially for urinary tract infections
  • Antispasmodic,
  • Carminative – prevents formation of gas in the gastrointestinal tract or facilitates the expulsion of said gas, thereby combating flatulence
  • Diuretic
  • Emmenagogue, stimulates blood flow in the pelvic area and uterus
  • Laxative
  • Sedative
  • Stimulant
  • Tonic

Modern scientific studies have revealed that many of the phytochemicals found in celery and other plants possess interesting biological activity (13).

It is important to note that most studies to date have used animal models and effects in humans have yet to be proven.

That said, there is some interesting evidence developing for various potential health benefits of celery.

Celery seed

Celery seed

Scientific evidence for health benefits of celery

Anti-hypertensive – lowers blood pressure

In animal studies, extracts of celery have been shown to reduce blood pressure (14, 15).

The flavone apigenin and the isobenzofuranone, 3-n-butylphthalide, are two of the phytochemicals best studied in this respect.

In one experiment, a very small amount of 3-n-butylphthalide, equivalent to that in four stalks of celery, lowered blood pressure by 12 to 14 per cent (16).

In animals, 3-n-butylphthalide appears to lower blood pressure by acting as both a diuretic and vasodilator (causes the blood vessels to expand) by influencing the production of hormone-like substances called prostaglandins, as well as acting in a similar manner to calcium-channel blockers (17).

Apigenin has also been shown to affect vasodilation by stimulating calcium channels in rat cell membranes (18).

Hypolipidemic – lowers cholesterol and triglycerides

3-n-butylphthalate has also been shown to lower blood cholesterol levels and reduce the formation of arterial plaque in preclinical studies (animal and in vitro studies) (19) (20).

This effect may increase the elasticity of blood vessels and also lead to lower blood pressure readings.

3-n-butylphthalate also appears to promote some effects on areas and systems of the brain that control vascular resistance (21).

Other studies in rats show that extracts of celery, containing terpenoid, tannin, alkaloid, glycoside, flavonoid and sterol phytochemicals, dose dependently inhibited total cholesterol, triglycerides, and low density lipoprotein levels, and significantly increased high density lipoprotein level (22).

Celery leaves

Celery leaves

Anti-inflammatory – reduces inflammation

Extracts of celery have been investigated and found to have significant anti-inflammatory activity in animal models (23) (24).

It is proposed that the anti-inflammatory activity of celery may form a basis for the reputation of the plant as a medicinal treatment for rheumatic and arthritic diseases.

Flavonoids are reported to affect the inflammatory process and to possess anti-inflammatory as well as immunomodulatory activity in vitro and in vivo.

Since nitric oxide produced by inducible nitric oxide synthase is one of the inflammatory mediators, the effects of celery extracts containing the flavonoid apiin as a major constituent, on inducible nitric oxide synthase expression and nitric oxide production were evaluated in a cell line (25).

The extract, and apiin alone, showed significant inhibitory activity on nitrite (NO) production.

Further tests on mice showed that the extract exerted anti-inflammatory activity in vivo, with a potency seven-times lower than that of indometacin, the non-steroidal anti-inflammatory drug used as reference (25).

Luteolin, another flavonoid found in celery, demonstrates a spectrum of biological activities.

Some Chinese researchers looked at the anti-inflammatory activity of luteolin in acute and chronic models in mice.  They observed suppression of inflammation in vivo (26).

Further experiments provided evidence that luteolin  may be a potent selective inhibitor of cyclooxygenase-2 (COX-2), which is the same target as that of the non-steroidal anti-inflammatory drugs (26).


Celery flowers


Many of the phytochemicals in celery are the subject of research for their potential anti-cancer activities (27)(28).

Luteolin, for example, is a flavonoid found in celery. It has been found to inhibit angiogenesis, induce apoptosis, prevent carcinogenesis in animal models, reduce tumour growth in vivo and to sensitize tumour cells to the cytotoxic effects of some anticancer drugs (29)(30).

Apigenin in celery has also been shown to regulate the cell cycle and thus may have benefits for cancer prevention (31).

Extracts of celery have been found to protect against chemically induced liver cancer in animal models (32).

Di(2-ethylhexyl) phthalate (DEHP), the most abundant phthalate in the environment, is known to be a reproductive toxicant. Researchers in Egypt investigated whether celery oil affects DEHP-induced testicular toxicity.  They found that celery oil partially prevented the damaging effects of this environmental toxin (33).

Antiulcerogenic – inhibits stomach ulcers

Celery oil was found to inhibit stomach ulcers in a dose-dependent manner in experimental rats, which was similar to that induced by omeprazole, a widely used drug for indigestion, acid reflux and peptic ulcers (34).  The major phyochemicals identified were β-pinene, camphene, cumene, limonene, α-thuyene, α-pinene, β-phellendrene, p-cymene, γ-terpinene, sabinene and terpinolene.

In another study with rats, pretreatment with celery extract produced dose-dependent reduction in all experimentally induced gastric lesions, with no toxic side effects or mortality over a period of 14 days. The phytochemical screening showed the presence of flavonoids, tannins, volatile oils, alkaloids, sterols and/or triterpenes. The authors concluded that celery extract significantly protects the gastric mucosa and suppresses the basal gastric secretion in rats, possibly through its antioxidant potential (35).

Celery stalks

Celery stalks

Anti-oxidant activity

Dietary plants contain variable chemical families and amounts of antioxidants.  Celery is no exception.

Antioxidants can eliminate free radicals and other reactive oxygen and nitrogen species, and these reactive species contribute to most chronic diseases. It is hypothesized that antioxidants originating from foods may work as antioxidants in their own right in vivo, as well as bring about beneficial health effects through other mechanisms, including acting as inducers of mechanisms related to antioxidant defence, longevity, cell maintenance and DNA repair (36).

The antioxidant content of celery products compared with broccoli and blueberries is shown below (36).

It is important to note the considerable variability between samples depending on environment, cultivar and type of product.

Product Antioxidant content
  mmol per 100g
Celery seeds 8.17
Celery leaves, dried 16.91
Celery raw, USA 0.06
Celery raw, Mali 0.81
Celery blanched 0
Broccoli raw, Norway 0.85
Broccoli raw, USA 0.25
Broccoli raw, Spain 0.68
Blueberries, cultivated USA 1.85
Blueberries, cultivated Norway 1.26

Anti-microbial activity

Celery is reported to have anti-bacterial and weak anti-fungal activity.

Celery extracts have been shown to have potent activity against Helicobacter pylori, a gram-negative bacterium found in the stomach (37).  H. pylori has been associated with chronic gastritis and gastric ulcers, conditions that were not previously believed to have a microbial cause. It is also linked to the development of duodenal ulcers and stomach cancer, though 80 per cent of people infected display no disease symptoms.

Essential oil of celery has also been shown to be strongly inhibitory against Escherichia coli and moderately inhibitory against Pseudomonas aeruginosa and Staphylococcus aureus (34).

Moderate anti-microbial activity has been shown by extracts of celery against multi-drug resistant Salmonella typhi (38).

This anti-microbial activity may explain the use of celery as a traditional herbal remedy for urinary tract and other infections.

Alzheimer’s disease

Alzheimer’s disease is an age-related, progressive neurodegenerative disorder that occurs gradually and results in memory, behaviour, and personality changes.

L-3-n-butylphthalide, an extract from seeds of celery, has been shown to have neuroprotective effects on ischaemic, vascular dementia, and amyloid-beta-infused animal models (39).

Treatment with L-3-n-butylphthalide significantly improved the spatial learning and memory deficits of transgenic mice compared to the controls.

It is believed to do this by inhibiting oxidative injury, neuronal apoptosis and glial activation, regulating amyloid-β protein precursor (AβPP) processing and reducing Aβ generation (40).

Celery root

Celery root

Multiple sclerosis

Multiple sclerosis is an inflammatory and demyelinating disease of the central nervous system which mainly affects young adults.

An animal model of multiple sclerosis called experimental allergic encephalomyelitis is used to test potential treatments for this disease.

In Iran, a herbal-marine product called MS14, containing 90 per cent Penaeus latisculatus (Western King prawn), 5 per cent Apium graveolens (celery), and 5 per cent Hypericum perforatum L (St John’s Wort) is used to slow down or halt the progression of multiple sclerosis.

Mice with induced brain inflammation were fed a diet containing MS14 (30 per cent) and monitored for 20 days. The disease was slowed down in the treated mice relative to the controls.  Moreover, while there were moderate to severe neuropathological changes in the controls, milder changes were seen in the mice treated with MS14 (41).

The precise role of celery in this remedy has not been elucidated and a great deal more work is required to determine its value for this indication.


Earlier I recounted the story of Calypso and Odysseus, full of desire in their celery-adorned cave.

This is not the only myth implicating celery as an aphrodisiac (42).

Central to the Celtic legend of Tristan and Isolde is a love potion, which they accidentally consume and are overcome with passion. This is unfortunate as Tristan is escorting Isolde on her way to marry his uncle.

Some say that their magic philtre contained celery root, though there is no direct evidence for this.  Love potions were usually made from mandrake (love apples), a poisonous member of the nightshade family, with other ingredients including orange, ambergris, vervain, briony and fern seed.

Tristan and Isolde drinking the love potion by John William Waterhouse

Tristan and Isolde drinking the love potion by John William Waterhouse

In the 18th century, Grimod de la Reyniere, an early food journalist, warned of celery’s aphrodisiac properties, advising that

it is not in any way a salad for bachelors

It is rumoured that Madame de Pompadour, maverick mistress of King Louis XV, invented a celery soup to inflame the desires of her royal lover.

So is there any scientific evidence to support these claims?

In 1979, two researchers reported that they had identified the volatile steroid, 5 alpha-androst-16-en-3-one, in the cytoplasm of parsnip and celery at concentrations of 8 nanograms per gram (8 parts per billion) (43).

This steroid is a pheromone found in both human male and female sweat and urine.  It is also found in high concentrations in the saliva of male pigs, and, when sniffed by a female pig that is in heat, results in the female assuming the mating stance.  Androstenone is the active ingredient in ‘Boarmate’, a commercial product made by DuPont sold to pig farmers to test sows for timing of artificial insemination.

mating pigs

Androstenone was the first mammalian pheromone to be identified and has thus been the subject of considerable study.

It turns out that the ability to smell androstenone is genetically determined (44).

Some people cannot smell it at all, whilst others can detect it down to levels of 0.2 parts per billion, which is 40 times lower than the concentration of androstenone reported in celery.

The speculation is that the smell of androstenone in celery acts as an aphrodisiac in sensitive individuals, though there is no direct evidence to confirm this.

The other speculation is that the action of certain phytochemicals in celery as potent vasodilators, as described above in the section on blood pressure (17), enhances male erectile function and thus sexual potency.

Again, however, there is no direct evidence to substantiate this hypothesis and, on the whole, scientists are dismissive of claims of the aphrodisiac properties of plants (45).

This does not necessarily mean that scientists are right – this is a notoriously difficult subject to study and research funding for it is hard to obtain – so, until more data are available, you will have to conduct your own experiments…

Adverse effects of celery

Celery produces phytochemicals called psoralens, which are furanocoumarins (46).

Psoralens are believed to be phytoalexins associated with celery resistance to pathogens.  High levels of psoralens are produced by celery infected with fungal pathogens.

When these compounds are exposed to long-wave UV light or sunlight the phototoxic furanocoumarins become carcinogenic agents; recognized as causally-related to skin cancer by the World Health Organization.

Photodermatitis of the fingers, hands and forearms is therefore a known occupational risk for celery handlers and field workers (47).

celery field workers

Workers in grocery stores and agricultural workers have also been reported to suffer skin reactions after handling celery and being exposed to UV light.

One case reported in the medical literature involved a 65-year-old woman who developed a severe, generalized phototoxic reaction following a visit to a suntan parlour. History taking revealed that she had consumed a large quantity of celery root one hour earlier.

Some people suffer allergic reactions to celery, caused by a protein called Api g 2; exposure can produce mild symptoms of skin irritation or cause potentially fatal anaphylactic shock.

Cooking celery does not destroy the proteins which cause the allergic reaction.

Allergy to celery seems to be linked to people with seasonal hay fever to birch and/or mugwort pollen (usually March/April) (47). This is called cross-reaction and is often an important cause of food allergies.

Celery allergy seems to be far more common in central Europe, mainly France, Switzerland and Germany, and less so in the UK and US, where peanut allergy is the most common.

Should you eat celery raw or cooked?

From a purely nutritional point of view, it is generally the case that storage and cooking of vegetables leads to loss of nutrients. The bioavailability of some nutrients, such as iron, may however be increased by cooking (48).

Loss of vitamins and minerals from vegetables is mainly because of extraction into the cooking liquid rather than their destruction. So provided that you consume the cooking liquid, as you do with soups and casseroles for example, you will still benefit from the nutrients.

Phytochemicals vary substantially in their stability to temperature, light and pH (49).

In general, the less food plants are processed and cooked the more phytochemicals remain active, but this is not always the case.

Spanish scientists investigated the influence of home cooking methods (boiling, microwaving, pressure-cooking, griddling, frying, and baking) on antioxidant activity in 20 vegetables (50).

Artichoke was the only vegetable that kept its very high antioxidant activity in all the cooking methods.

Highest losses of antioxidant activity were observed in cauliflower after boiling and microwaving; pea after boiling; courgette (zucchini) after boiling and frying; and swiss chard and pepper with all methods.

Beetroot, green bean, and garlic kept their antioxidant activity after most cooking treatments.

Celery reportedly increased its antioxidant capacity in all the cooking methods, except boiling when it lost 14 per cent.

Whether to eat celery raw or cooked is a matter of personal choice and depends on your preferences, your constitution, your condition at the time and your external environment.

In hot weather, raw celery is very cooling.

When the weather is cooler or if your digestive system is weak, it may be better to eat cooked celery in a soup or casserole.

Recipes with celery

Raw celery can be used in salads, as crudites to eat with vegetable dips, and as an ingredient in a refreshing green juice.

Cooked celery can be used in soups, sauces and casseroles.

Celery, cucumber, apple, parsley and lime juice

Green juices are a great way to include a wider variety of vegetables in your diet, are packed with nutrients and easy to digest.

Here is a delicious recipe for a refreshing, cooling green juice, ideal for a hot day.

Please click here for details: Recipe for celery, cucumber, apple, parsley and lime juice.

celery cucumber apple lime parsley juice

Celery, cucumber, apple, parsley and lime juice – Jane Philpott at

Pressed salad with celery, cucumber, fennel and radish

On the hottest days, we need to balance the external heat by using raw vegetables with cooling properties.  This crunchy, tangy salad using celery is easy to prepare and ideal for al fresco meals.

Please click here for details: Recipe for celery, fennel, cucumber and radish pressed salad

close up celery fennel cucumber radish salad

Celery and sweetcorn chowder

This simple, sweet, summery soup recipe can be served warm or cold.  It soothes the digestive system and helps to relax you at the start of a meal.

Please click here for details: Recipe for celery and sweetcorn chowder.

celery and sweetcorn chowder

Celery and sweetcorn chowder – Jane Philpott at

And finally…

Given that I have just devoted a whole blog post to extolling the virtues of celery, do I think you should rush off and start buying wholesale quantities?

Of course not.

That would be silly.


The reason is that I could choose almost any food plant and write a similar article about all the wonderful nutrients and phytochemicals it contains and the beneficial effects of these substances on your health.

All plants contain an incredible array of substances with powerful biological activity, which protect our bodies from damage and help to prevent and treat chronic disease.

These substances vary from plant to plant and it is the COMBINATION of all of them, operating together in a coordinated and often synergistic manner to regulate gene expression, which results in optimum health.

So just make sure you eat as many whole plant foods as possible and you will maximise your chances of living a long and healthy life.

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(1)  Rubatzky, V.E. and Yamaguchi, M. (1997), World Vegetables, second edition, N.Y. Chapman & Hall, pp. 432–443.

(2) Homer, the Odyssey, Book V, 71-82

(3) Domeena C. Renshaw. Aphrodisiacs: The Science and the Myth. JAMA. 1986;255(1):98-99. doi:10.1001/jama.1986.03370010108037

(4) D. Zohary and M. Hopf, Domestication of Plants in the Old World, (3rd ed. 2000) p.202.

(5) U.S. Department of Agriculture, Agricultural Research Service. 2012. USDA National Nutrient Database for Standard Reference, Release 25. Nutrient Data Laboratory Home Page,

(6) Mikkelsen PB, Toubro S, & Astrup A (2000). Effect of fat-reduced diets on 24-h energy expenditure: comparisons between animal protein, vegetable protein, and carbohydrate. The American journal of clinical nutrition, 72 (5), 1135-41 PMID: 11063440

(7) Raben A, Christensen NJ, Madsen J, Holst JJ, & Astrup A (1994). Decreased postprandial thermogenesis and fat oxidation but increased fullness after a high-fiber meal compared with a low-fiber meal. The American journal of clinical nutrition, 59 (6), 1386-94 PMID: 8198065

(8) Westerterp, K. (2004). Diet induced thermogenesis Nutrition & Metabolism, 1 (1) DOI: 10.1186/1743-7075-1-5

(9) Dr Duke’s Phytochemical and Ethnobotanical Databases

(10) CU JIAN-QIN, ZHONG JZ and PAR P (1990) GCMs analysis of the essential oil of celery seed. Indian Perfumer. 34(1–4), vi-vii.

(11) Grieve, M. A Modern Herbal. 1931. Jonathan Cape Ltd, London.

(12) Duke, J.A. The Green Pharmacy. Herbal remedies for common diseases and conditions. Rodale International Ltd; New edition edition (3 Jan 2003)

(13) Higdon, J. and Drake, V.J.  An Evidence-based Approach to Phytochemicals and Other Dietary Factors. Linus Pauling Institute,  Hardcover (2013), 2nd Edition, 368 pp.

(14) Ma X, He D, Ru X, Chen Y, Cai Y, Bruce IC, Xia Q, Yao X, Jin J. Apigenin, a plant-derived flavone, activates transient receptor potential vanilloid 4 cation channel. Br J Pharmacol. 2012 May;166(1):349-58. doi: 10.1111/j.1476-5381.2011.01767.x. PubMed PMID: 22049911; PubMed Central PMCID: PMC3415659.

(15) Moghadam MH, Imenshahidi M, Mohajeri SA. Antihypertensive effect of celery seed on rat blood pressure in chronic administration. J Med Food. 2013 Jun;16(6):558-63. doi: 10.1089/jmf.2012.2664. Epub 2013 Jun 4. PubMed PMID: 23735001; PubMed Central PMCID: PMC3684138.

(16) Le QT, Elliott WJ. Hypotensive and hypocholesterolemic effects of celery oil may be due to BuPh. Clin Res.1991;39:173A.

(17) Tsi D, Tan BKH. Cardiovascular pharmacology of 3-n-butylphthalide in spontaneously hypertensive rats. Phytotherapy Research. 1997;11:576-582.

(18) Ma X, He D, Ru X, Chen Y, Cai Y, Bruce IC, Xia Q, Yao X, Jin J. Apigenin, a plant-derived flavone, activates transient receptor potential vanilloid 4 cation channel. Br J Pharmacol. 2012 May;166(1):349-58. doi: 10.1111/j.1476-5381.2011.01767.x. PubMed PMID: 22049911; PubMed Central PMCID: PMC3415659.

(19) Le QT, Elliott WJ. Dose-response relationship of blood pressure and serum cholesterol to 3-n-butylphthalide, a component of celery oil. Clin Res. 1991;39:750A.

(20) Mimura Y, Kobayashi S, Naitoh T, Kimura I, Kimura M. The structure-activity relationship between synthetic butylidenephthalide derivatives regarding the competence and progression of inhibition in primary cultures proliferation of mouse aorta smooth muscle cells. Biol Pharm Bull. 1995;18(9):1203-1206.

(21) Yu SR, Gao NN, Li LL, Wang ZY, Chen Y, Wang WN. The protective effect of 3-butyl phthalide on rat brain cells. Yao Hsueh Hsueh Pao. 1988;23(9):656-661.

(22) Iyer D, Patil UK. Effect of chloroform and aqueous basic fraction of ethanolic extract from Apium graveolens L. in experimentally-induced hyperlipidemia in rats. J Complement Integr Med. 2011 Sep 27;8. doi:pii: /j/jcim.2011.8.issue-1/1553-3840.1529/1553-3840.1529.xml. 10.2202/1553-3840.1529. PubMed PMID: 22718672.

(23) Lewis, D.A.; Tharib, S.M.; Bryan, G.; Veitch, A. Pharmaceutical Biology, 1985, Vol. 23, No. 1 : Pages 27-32. The Anti-inflammatory Activity of Celery Apium graveolens L. (Fam. Umbelliferae) (doi: 10.3109/13880208509070685)

(24) Al-Hindawi MK, Al-Deen IH, Nabi MH, Ismail MA. Anti-inflammatory activity of some Iraqi plants using intact rats. J Ethnopharmacol. 1989 Sep;26(2):163-8. PubMed PMID: 2601356.

(25) Mencherini T, Cau A, Bianco G, Della Loggia R, Aquino RP, Autore G. An extract of Apium graveolens var. dulce leaves: structure of the major constituent, apiin, and its anti-inflammatory properties. J Pharm Pharmacol. 2007 Jun;59(6):891-7. PubMed PMID: 17637182.

(26) Ziyan L, Yongmei Z, Nan Z, Ning T, Baolin L. Evaluation of the anti-inflammatory activity of luteolin in experimental animal models.Planta Med. 2007 Mar;73(3):221-6. Epub 2007 Mar 12. PubMed PMID: 17354164.

(27) Christensen LP, Brandt K. Bioactive polyacetylenes in food plants of the Apiaceae family: occurrence, bioactivity and analysis. J Pharm Biomed Anal. 2006 Jun 7;41(3):683-93. Epub 2006 Mar 7. Review. PubMed PMID: 16520011.

(28) Ren S, Lien EJ. Natural products and their derivatives as cancer chemopreventive agents. Prog Drug Res. 1997;48:147-71. Review. PubMed PMID: 9204686.

(29) López-Lázaro M. Distribution and biological activities of the flavonoid luteolin. Mini Rev Med Chem. 2009 Jan;9(1):31-59. Review. PubMed PMID: 19149659.

(30) Lim do Y, Jeong Y, Tyner AL, Park JH. Induction of cell cycle arrest and apoptosis in HT-29 human colon cancer cells by the dietary compound luteolin. Am J Physiol Gastrointest Liver Physiol. 2007 Jan;292(1):G66-75. Epub 2006 Aug 10. PubMed PMID: 16901994.

(31) Meeran SM, Katiyar SK. Cell cycle control as a basis for cancer chemoprevention through dietary agents. Front Biosci. 2008 Jan 1;13:2191-202. Review. PubMed PMID: 17981702; PubMed Central PMCID: PMC2387048.

(32) Sultana S, Ahmed S, Jahangir T, Sharma S. Inhibitory effect of celery seeds extract on chemically induced hepatocarcinogenesis: modulation of cell proliferation, metabolism and altered hepatic foci development. Cancer Lett. 2005 Apr 18;221(1):11-20. PubMed PMID: 15797622.

(33) Madkour NK. The beneficial role of celery oil in lowering of di(2-ethylhexyl) phthalate-induced testicular damage. Toxicol Ind Health. 2012 Nov 16. [Epub ahead of print] PubMed PMID: 23160384.

(34) Baananou S, Bouftira I, Mahmoud A, Boukef K, Marongiu B, Boughattas NA. Antiulcerogenic and antibacterial activities of Apium graveolens essential oil and extract. Nat Prod Res. 2013 Jun;27(12):1075-83. doi: 10.1080/14786419.2012.717284. Epub 2012 Aug 30. PubMed PMID: 22934666.

(35) Al-Howiriny T, Alsheikh A, Alqasoumi S, Al-Yahya M, ElTahir K, Rafatullah S. Gastric antiulcer, antisecretory and cytoprotective properties of celery (Apium graveolens) in rats. Pharm Biol. 2010 Jul;48(7):786-93. doi: 10.3109/13880200903280026. PubMed PMID: 20645778.

(36) Carlsen MH, Halvorsen BL, Holte K, Bøhn SK, Dragland S, Sampson L, Willey C, Senoo H, Umezono Y, Sanada C, Barikmo I, Berhe N, Willett WC, Phillips KM, Jacobs DR Jr, Blomhoff R. The total antioxidant content of more than 3100 foods, beverages, spices, herbs and supplements used worldwide. Nutr J. 2010 Jan 22;9:3. doi: 10.1186/1475-2891-9-3. PubMed PMID: 20096093; PubMed Central PMCID: PMC2841576.

(37) Zhou Y, Taylor B, Smith TJ, Liu ZP, Clench M, Davies NW, Rainsford KD. A novel compound from celery seed with a bactericidal effect against Helicobacter pylori. J Pharm Pharmacol. 2009 Aug;61(8):1067-77. doi: 10.1211/jpp/61.08.0011. PubMed PMID: 19703351.

(38) Rani P, Khullar N. Antimicrobial evaluation of some medicinal plants for their anti-enteric potential against multi-drug resistant Salmonella typhi. Phytother Res. 2004 Aug;18(8):670-3. PubMed PMID: 15476301.

(39) Peng Y, Sun J, Hon S, Nylander AN, Xia W, Feng Y, Wang X, Lemere CA. L-3-n-butylphthalide improves cognitive impairment and reduces amyloid-beta in a transgenic model of Alzheimer’s disease. J Neurosci. 2010 Jun 16;30(24):8180-9. doi: 10.1523/JNEUROSCI.0340-10.2010. PubMed PMID: 20554868.

(40) Peng Y, Hu Y, Xu S, Li P, Li J, Lu L, Yang H, Feng N, Wang L, Wang X. L-3-n-butylphthalide reduces tau phosphorylation and improves cognitive deficits in AβPP/PS1-Alzheimer’s transgenic mice. J Alzheimers Dis. 2012;29(2):379-91. doi: 10.3233/JAD-2011-111577. PubMed PMID: 22233765.

(41) Tafreshi AP, Ahmadi A, Ghaffarpur M, Mostafavi H, Rezaeizadeh H, Minaie B, Faghihzadeh S, Naseri M. An Iranian herbal-marine medicine, MS14, ameliorates experimental allergic encephalomyelitis. Phytother Res. 2008 Aug;22(8):1083-6. doi: 10.1002/ptr.2459. PubMed PMID: 18570265.

(42) Mark Douglas Hill. The Aphrodisiac Encycopedia – a compendium of culinary come-ons. Square Peg, 6 October 2011.

(43) Claus R, Hoppen HO. The boar-pheromone steroid identified in vegetables. Experientia. 1979 Dec 15;35(12):1674-5. PubMed PMID: 520500.

(44) Wysocki CJ, Beauchamp GK. Ability to smell androstenone is genetically determined. Proc Natl Acad Sci U S A. 1984 Aug;81(15):4899-902. PubMed PMID: 6589634; PubMed Central PMCID: PMC391599.

(45) Domeena C. Renshaw, MD.  Aphrodisiacs: The Science and the Myth  JAMA. 1986;255(1):98-99. doi:10.1001/jama.1986.03370010108037

(46) Alan Crozier, Michael N. Clifford, Hiroshi Ashihara (Editors). Plant Secondary Metabolites: Occurrence, Structure and Role in the Human Diet. Wiley Online Library. Published Online: 12 NOV 2007; Print ISBN: 9781405125093; Online ISBN: 9780470988558; DOI: 10.1002/9780470988558

(47) Deleo VA. Photocontact dermatitis. Dermatol Ther. 2004;17(4):279-88. Review. PubMed PMID: 15327473.

(48) Gadermaier G, Hauser M, Egger M, Ferrara R, Briza P, Santos KS, Zennaro D, Girbl T, Zuidmeer-Jongejan L, Mari A, Ferreira F. Sensitization prevalence, antibody cross-reactivity and immunogenic peptide profile of Api g 2, the non-specific lipid transfer protein 1 of celery. PLoS One. 2011;6(8):e24150. doi: 10.1371/journal.pone.0024150. Epub 2011 Aug 29. PubMed PMID: 21897872; PubMed Central PMCID: PMC3163685.

(49) Brijesh K. Tiwari (Editor), Nigel P. Brunton (Editor), Charles Brennan (Editor). Handbook of Plant Food Phytochemicals: Sources, Stability and Extraction [Hardcover]. Wiley-Blackwell (22 Feb 2013)

(50) Jiménez-Monreal AM, García-Diz L, Martínez-Tomé M, Mariscal M, Murcia MA. Influence of cooking methods on antioxidant activity of vegetables. J Food Sci. 2009 Apr;74(3):H97-H103. doi: 10.1111/j.1750-3841.2009.01091.x. PubMed PMID: 19397724.

Angelina Jolie, cancer, your genes and your fate


Angelina Jolie

It must have taken courage for Angelina Jolie to tell the world, via an article in the New York Times, that she had undergone a preventive double mastectomy.  A-list actresses are usually judged on their body image as much as on their acting ability.

Angelina made this choice because her doctors had warned her that she has an 87% risk of developing breast cancer and a 50% risk of getting ovarian cancer because her mother died of breast cancer and she carries the BRCA1 gene.

I respect Angelina for making a choice which felt right for her and her family.

That is all any of us can do when faced with difficult decisions and the tsunami of judgement that has greeted her article is regrettable.

The story does, however, raise fascinating questions about whether we are really at the mercy of our genes.

Do our genes dictate our fate or do we have any power over them?

I want to tell you what I think and why.

dividing line

In 1868, Friedrich Miescher discovered the presence of DNA, and in 1953, James Watson and Francis Crick discovered its molecular structure, with the help of Maurice Wilkins, Rosalind Franklin, Erwin Chargaff and Linus Pauling.

DNA Watson and Crick

In the years that followed, scientists have learned a great deal about how this genetic code dictates who we are.

Our DNA – specifically the 25,000 genes identified by the Human Genome Project – is now widely regarded as the instruction book for the human body.

Genetic science has attracted billions of dollars of research funding and was heralded as the key to understanding and curing diseases like cancer.

The trouble is that despite all the money that has been poured into it, our knowledge of genetics has not yielded the promised revolutionary cures for cancer on a widespread scale.

Whilst the latest official report on the “War on Cancer” from America indicates that death rates for all cancers combined decreased by 1.5 percent per year from 2000 to 2009 [1], this is no greater than the previous five year period.

Deaths are still rising for certain cancer types including liver, pancreatic, uterus and, among men, melanoma.  Rates of human papillomavirus (HPV)–related cancers, such as oral, anal, vaginal, vulval, penis and cervical, also remain stubbornly high despite the availability of a vaccine.  And many epithelial cancers (carcinomas) and effectively all mesenchymal cancers (sarcomas) remain incurable.

There were decreases in new breast cancer cases about a decade ago, as many women stopped using hormone therapy after menopause.  Since then, overall breast cancer incidence has reached a plateau, and rates have increased among black women.

The decrease in cancer mortality is driven largely by the decrease in cancer incidence, which is mostly because of the decrease in smoking [1]. Smoking can cause more than a dozen cancers, including lung, head, neck, bladder and mouth.

smoking addiction

Although improvements in screening and treatment for breast and some other cancers have cut death rates, most of the expensive new drugs prolong survival for no more than three or four months on average.

James Watson, famous for his part in the discovery of the structure of DNA, wrote in a recent edition of the Royal Society Journal “Open Biology”[2]:

Even though an increasing variety of intelligently designed, gene-targeted drugs now are in clinical use, they generally only temporarily hold back the fatal ravages of major cancers such as those of the lung, colon and breast that have become metastatic and gone beyond the reach of the skilled surgeon or radiotherapist.  Even though we will soon have comprehensive views of how most cancers arise and function at the genetic and biochemical level, their ‘curing’ seems now to many seasoned scientists an even more daunting objective than when the ‘War on Cancer’ was started by President Nixon in December 1971.

When we look at the decades of investments, the cost of treatments, the number of researchers and journals, and at the number of people who continue to die, we have to ask if we are barking up the wrong tree.

I believe we are.

The reality is that as fast as scientists find a ‘magic bullet’ to block a particular protein or cellular pathway to decimate cancer cells, the cancer cells find a way to circumvent the therapy, thrive and proliferate.

How do they do this?

dividing line

Well it turns out that DNA, the genome, is only half the story.

This should not be a surprise given that chromosomes contain only 50 per cent DNA; the other 50 per cent is protein.

Within each chromosome, DNA is wrapped around proteins called histones.  Both DNA and histones are covered in millions of tiny chemical tags.

This second layer of structure comprising histones and chemical tags is called the epigenome – meaning literally “above the genome”.

The epigenome shapes the physical structure of the genome, the DNA.  It tightly wraps inactive genes making them unreadable.  It relaxes around active genes making them easily accessible.



Different sets of genes are active in different cell types.

A human liver cell, for example, contains the same DNA as a brain cell, yet somehow it knows to code only those proteins needed for the functioning of the liver.  Those instructions are found not in the letters of the DNA itself but on the array of chemical tags which are part of the epigenome.

The DNA code remains fixed for life but the epigenome is flexible.

Epigenetic tags react to signals within the cell environment and to signals from the outside environment, such as diet, stress and our thoughts.

The epigenome adjusts the expression of specific genes in response to our rapidly changing environment.

How does this work?

dividing line

In the 1980s, researchers discovered that the answer to this question lay in specific chemical modifications to genomic DNA and its associated histone proteins, without changing the DNA itself at all.

What are these modifications?

In school biology lessons we learn that DNA is built from four different units called nucleotides: adenine, cytosine, guanine, and thymine.

In one type of epigenetic modification, a methyl group (one carbon atom linked to three hydrogen atoms -CH3) is added to specific cytosine bases of the DNA with help from enzymes.

Microsoft PowerPoint - Presentation1 (3) [Read-Only]

DNA methylation. Credit: Adrian Bird

This process, called DNA methylation, is known to play a key role in both development and disease.

Methylation of DNA affects the way the molecule is shaped and, consequently, regulates which genes are available to be ‘read’ or transcribed.

Recently, another type of epigenetic modification of DNA was discovered: the addition of a hydroxymethyl group (–CH2–OH) to specific cytosine bases of DNA.

Histone proteins can also be modified in a number of ways; in addition to methylation, they can be modified with acetyl groups (acetylation), phosphate groups (phosphorylation), ubiquitin proteins (ubiquitylation), and SUMO proteins (sumoylation).

But epigenetic phenomena are not restricted to DNA methylation and various types of histone modifications.

Scientists have found that RNA molecules themselves can also regulate DNA directly by physically blocking or influencing the reading of DNA sequences.

These RNA molecules aren’t the classic messenger RNA (mRNA) molecules we learn about in school biology that carry the information from DNA in the nucleus to the cytoplasm of a cell.  Rather, these RNA molecules – called antisense RNAs, microRNAs, and noncoding RNAs – stay primarily within the nucleus, where they induce changes in DNA function.

It is not yet fully understood how these RNA molecules work but it appears they may bind to histone proteins and/or help to turn off gene promoters.

So how does the environment interact with the epigenome and influence our genes?

dividing line

One of the most exciting discoveries of modern science is that our DNA, the genome, responds dynamically to the environment.

Stress, diet, behaviour, toxins and other factors activate the chemical tags or switches that turn our genes on and off.

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Nutrition is one of the easier environmental factors to study with respect to epigenetic changes and is receiving considerable research effort.

One of the most stunning examples of the effect of nutrition on gene expression was an experiment conducted at Duke University in 2000 [3].

Randy Jirtle and his postdoctoral student Robert Waterland took pairs of fat, yellow mice which carry the agouti gene, which is also found in humans.  This gene makes the rats extremely hungry and renders them prone to obesity, diabetes and cancer.


Typically, when agouti mice breed, most of the offspring are identical to the parents: yellow, fat and susceptible to disease.

In this experiment, the researchers simply changed the diet of the mothers.

Before conception and during pregnancy, one set of mice were fed a diet containing nutrients rich in methyl groups, for example, folate and the B vitamins.  These molecules are found in many plant foods and in supplements given to pregnant women.  The other set of genetically identical mice were fed a regular diet low in these nutrients over the same time period.

Mice with the agouti gene (picture from University of Utah)

Mice with the agouti gene (picture from University of Utah)

To the researchers’ amazement, the mothers fed the methyl rich diet produced brown, slim, healthy offspring, whereas the mothers on the normal diet produced the typical yellow, fat and sickly offspring.  The only difference between the two was the diet the mothers were given.

Methyl groups from the dietary supplements (folic acid, vitamin B12, choline, and betaine) bound to the DNA of the mice, increasing DNA methylation and preventing the agouti gene from being expressed.

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Chemicals and additives that enter our bodies can also affect the epigenome.

Bisphenol A (BPA) is a compound used to make polycarbonate plastic.  It is in many consumer products including water bottles and the lining of tin cans.

When pregnant yellow agouti mothers were fed BPA, more yellow, unhealthy babies were born than normal.  Exposure to BPA during early development had caused decreased methylation of the agouti gene.

However, when BPA-exposed, pregnant yellow mice were fed a diet containing B vitamins, folate, choline and betaine, which are rich in methyl groups, the offspring were predominantly brown.  The maternal nutrient supplementation had counteracted the negative effects of exposure to a genotoxic chemical [4].

Mice with the agouti gene

Mice with the agouti gene fed with Bisphenol A

The father’s diet may be important too.

A Swedish paper published in 2007 [5] provided evidence from historical records that a shortage of food for grandfathers was associated with extended lifespan of their grandchildren.  Food abundance, on the other hand, was associated with a greatly shortened lifespan of the grandchildren due to diabetes and heart disease.

This suggests the possibility that during this critical period of development for the grandfather, epigenetic mechanisms are “capturing” nutritional information about the environment to pass on to the next generation.

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Honey bees, too, provide a beautiful example of the power of nutrition over gene expression.

The larvae that develop into workers and queens are genetically identical.  Larvae destined to become queens, however, are fed a diet of royal jelly in a special compartment in the hive called a queen cup.

Queen cup

Queen cup

Royal jelly is a complex, protein-rich substance secreted from glands on the heads of worker bees.   Consumption of royal jelly enables the queen to develop functional ovaries and a larger abdomen for egg laying, while worker bees remain sterile.

The queen also develops different behaviours from those of the workers, becoming more aggressive, looking for mates and communicating using sounds.  The queen is fed royal jelly exclusively for the rest of her life.

In a recent series of experiments, scientists determined that royal jelly silences a key gene (Dnmt3), which codes for an enzyme involved in genome-wide gene silencing [6].  When Dnmt3 is active in bee larvae, the queen genes are epigenetically silenced and the larvae develop into the default “worker” variety.  But when royal jelly turns Dnmt3 off, certain genes jump into action that turn the larvae into queens.

This is all very interesting but how is it relevant to cancer?

dividing line

Cancer develops when a cell becomes abnormal and begins to grow out of control.

Normal cells and cancer cells

Normal cells and cancer cells (picture from University of Utah)

Cancer can begin when a mutation changes a cell’s DNA sequence.  We know that mutations in at least several hundred human genes (out of a total of 25 000 genes) can lead to the abnormal cell growth and division process that generates human cancer [7].

But cancer cells also have abnormal epigenomes.

In many cancers, some genes are turned up and some are turned down – often in the same cells.  Cancer is just one in a growing number of diseases that are being linked to changes in the epigenome.

Some cancer cells have a lower level of methylation (more active DNA) than healthy cells.

less methyl - genes on

Too little methylation causes:

  • activation of genes that promote cell growth
  • chromosome instability – highly active DNA is more likely to be duplicated, deleted and moved to other locations
  • loss of imprinting.  For most genes, we inherit two working copies – one from each parent. But with imprinted genes, we inherit only one working copy. Depending on the gene, either the copy from your mother or your father is epigenetically silenced.  Silencing usually happens through the addition of methyl groups during egg or sperm formation.

Cancer cells can also have genes that have more methyl (are less active) than normal.

More methylation - genes off (picture from University of Utah)

The types of genes that are turned down in cancer cells:

  • keep cell growth in check
  • repair damaged DNA
  • initiate programmed cell death

But here is the real magic.

Unlike mutations, DNA methylation and histone modifications are reversible.

Researchers are thus exploring drug therapies that can change the epigenetic profiles of cancer cells.  One challenge with epigenetic therapies is figuring out how to target drugs to the right genes in the right tissues.

It is for example possible to reactivate dormant tumour-suppressor genes with drugs which remove methyl groups from histone proteins [8].

DNA demethylating drugs in low doses have clinical activity against some tumours, for example, leukaemia, but have not yet been shown to have activity against solid tumours [9].

A key problem is that these demethylating agents are non-specific, often toxic and can potentially exert their effects in healthy tissues paradoxically causing new tumours to develop.

Other drugs targeted at the epigenome are the histone deacetylase (HDAC) inhibitors.

These can induce differentiation, cell-cycle arrest, and programmed cell death (apoptosis) in vitro, although it has not been possible to pinpoint a specific mechanism that explains these effects [10].

In clinical trials, HDAC inhibitors are associated with a low incidence of adverse events.  The first drug of this type, suberoylanilide hydroxamic acid (vorinostat),has been approved by the Food and Drug Administration for the treatment of cutaneous T-cell lymphoma [11].  The efficacy of HDAC inhibitors in the treatment of other tumours is limited.

Research on manipulating specific targets in the epigenome with drugs is, in my view, likely to be as doomed to failure as the decades of research looking for drugs which target the genome.

This is because complex biological systems like the human body operate through a large number of simultaneous reactions occurring in a highly integrated and concerted manner.

The body has multiple back-up systems in case one system is bypassed.

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Nutrition, epigenetics and cancer

In addition to drug research, there is also considerable interest in the way nutrients affect the epigenome in relation to cancer [12] [13] [14] [15].

Extensive review of the highest quality papers in the scientific literature by a team of international experts on behalf of the World Cancer Research Fund has led to the view that at least 30-40 per cent of cancers potentially can be avoided through dietary modification [16].

Many bioactive components have been identified in food, which are protective at different stages of cancer formation.  Diet has been implicated in many pathways involved in carcinogenesis, including apoptosis, cell cycle control, differentiation, inflammation, angiogenesis, DNA repair, and carcinogen metabolism [12].  These are also processes likely to be regulated by DNA methylation and other epigenetic events.

A host of bioactive substances in the diet, from alcohol to zinc, have been shown to modulate DNA methylation and cancer susceptibility [12] [16].

Dietary factors that are involved in one-carbon metabolism provide the most compelling data for the interaction of nutrients and DNA methylation because they influence the supply of methyl groups and therefore the biochemical pathways of methylation processes. These nutrients include vitamin B12, vitamin B6, folate, methionine, and choline.


A large number of epidemiologic and clinical studies suggest that dietary folate intake and blood folate concentrations are inversely associated with colorectal cancer risk [17].

Alcohol consumption increases breast cancer incidence by 41 percent for women consuming 30-60 g/day alcohol compared to non-drinking women [18].  Alcohol consumption has been shown to alter folate metabolism and increase cancer susceptibility [19] [20].

adults drinking

Sulforaphanes from broccoli, diallyl disuphides from garlic and resveratrol in wine, have been shown (in vitro and in vivo) to alter epigenetic processes with positive consequences for cell function, including control of proliferation, upregulated apoptosis and a reduction in inflammation [21].


Green tea polyphenols have been shown to inhibit carcinogenesis through effects on DNA methylation in many animal models [22].

green tea

Soy phytoestrogens, such as genistein, have been shown to prevent certain mammary and prostate cancers via protective DNA methylation [12].

Apigenin in parsley, curcumin in turmeric, and coffee polyphenols are reported to inhibit DNA methyltransferase enzyme activity in various cancer models [23] [24].

soy turmeric parsley

Zinc deficiency, selenium deficiency and vitamin A excess have been associated with DNA hypomethylation in rat liver, whilst vitamin C deficiency caused hypermethylation in lung cancer cells [12].

There are many more examples but these few serve to illustrate the fact that many dietary components interact in a complex and dynamic manner with the epigenome to alter gene expression and susceptibility to cancer and other diseases.

dividing line

Whilst studying the effect of individual nutrients on epigenetic processes is instructive, it is far too simplistic.  Food contains an extraordinary array of nutrients and other substances that work together in concert to create health or disease.

china study

Professor T. Colin Campbell’s thought-provoking book “The China Study” opened up the scientific literature on the effect of diet on health to a wide audience.  He explained the evidence showing that a plant-based diet is the healthiest way to eat, dramatically reducing the risk of a range of chronic diseases, such as arthritis, diabetes, heart disease and many cancers.

This dietary effect is due to the consumption of myriad beneficial substances found in whole plant foods, which interact with the epigenome to ensure that our genes are switched on and off correctly. 

Colin Campbell expands on this theme in his new book “Whole: Rethinking the Science of Nutrition”, due out on 23 May 2013.  He argues that nutritional science, long stuck in a reductionist mindset, is at the cusp of a revolution.  He writes:

The traditional “gold standard” of nutrition research has been to study one chemical at a time in an attempt to determine its particular impact on the human body. These sorts of studies are helpful to food companies trying to prove there is a chemical in milk or pre-packaged dinners that is “good” for us, but they provide little insight into the complexity of what actually happens in our bodies or how those chemicals contribute to our health.

Diet is, however, only one of many environmental influences on the way our genes behave.

dividing line

There is also a growing body of scientific research surfacing from the medical literature showing that our thoughts and emotions directly affect expression of our genes.

Mind over Medicine Lissa Rankin

Lissa Rankin MD’s new book “Mind over Medicine” is an excellent and readable synopsis of some of the key studies in this area and is thoroughly recommended.

David Hamilton PhD is an organic chemist who used to work in pharmaceutical research inventing drugs for cardiovascular disease.  He left his job because he became more interested in the placebo effect than the effect of drugs he was trying to invent.  David has also written some fascinating books on the science of how the mind affects the body, including “How Your Mind Can Heal Your Body”.

Bruce Lipton PhD, a developmental cell biologist and former Professor of Anatomy at University of Wisconsin School of Medicine, was one of the original researchers in the field of epigenetics and opened my eyes to its exciting advances in his book “The Biology of Belief”.

Dean Ornish MD, Clinical Professor of Medicine at the University of California, San Francisco, has been actively researching the effects of lifestyle factors, including diet, thoughts, social interactions and love, on cancer and other diseases for over 35 years.

The research that he and his colleagues conducted has been published in the Journal of the American Medical Association, The Lancet, Proceedings of the National Academy of Sciences, Circulation, The New England Journal of Medicine, the American Journal of Cardiology, The Lancet Oncology, and elsewhere.


This research is not pseudoscience woo-woo.  It is high quality, properly designed and controlled, peer-reviewed science published in some of the most prestigious medical journals in the world.  And it is only the tip of the iceberg.

The knowledge and understanding we are gaining from modern scientific research in the field of epigenetics has profound implications.

It demonstrates that we do not have to be the victims of our genes.

Genes may predispose us to certain health conditions but their presence does not inevitably determine our health outcomes.

Our environment and lifestyle choices – the thoughts we think, the food and drink we consume, our physical activity, whether or not we smoke, our relationships, our work, our finances, our level of stress, our stewardship of the earth – all interact with our genes to determine our fate.

The truth is that all of us will die one day.

While we are here, though, it is about having a life, not just living.

So embrace your power, trust your instincts about what is best for you, and do not allow fear-mongers on both sides of controversial debates, like the one about Angelina Jolie, scare you to death.

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[1] Jemal, A. et al (2013).  Annual Report to the Nation on the Status of Cancer, 1975–2009, Featuring the Burden and Trends in Human Papillomavirus (HPV)–Associated Cancers and HPV Vaccination Coverage Levels.  JNCI J Natl Cancer Inst (2013) doi: 10.1093/jnci/djs491 First published online: January 7, 2013

[2] Watson, J.  Oxidants, antioxidants and the current incurability of metastatic cancers.  Open Biol. 2013 3, 120144, published online 8 January 2013

[3] Waterland RA, Jirtle RL. Transposable elements: targets for early nutritional effects on epigenetic gene regulation. Mol Cell Biol 2003;23(15):5293–5300

[4] Dolinoy D.C., Huang D., Jirtle R.L. (2007). Maternal nutrient supplementation counteracts bisphenol A-induced DNA hypomethylation in early development. PNAS, 104: 13056-13061.

[5] Kaati G., Bygren L.O., Pembrey M., Sjostrom M. (2007). Transgenerational response to nutrition, early life circumstances and longevity. European Journal of Human Genetics, 15: 784-790.

[6] Kucharski R., Maleszka J., Foret S., Maleszka R. Nutritional Control of Reproductive Status in Honeybees via DNA Methylation (2008). Science, 319: 1827-1830 (registration required).

[7] Jones S, Vogelstein B, Velculescu VE, Kinzler KW. 2008 Core signaling pathways in human pancreatic cancers revealed by global genomic analyses. Science 321, 1801. (doi:10.1126/science.1164368)

[8] Esteller, M.  Epigenetics in cancer.  N Engl J Med 2008;358:1148-59.

[9] Mack GS. Epigenetic cancer therapy makes headway. J Natl Cancer Inst 2006; 98:1443-4.

[10] Bolden JE, Peart MJ, Johnstone RW.Anticancer activities of histone deacetylase inhibitors. Nat Rev Drug Discov 2006;5:769-84.

[11] Marks PA, Breslow R. Dimethyl sulfoxide to vorinostat: development of this histone deacetylase inhibitor as an anticancer drug. Nat Biotechnol 2007;25:84-90.

[12] Davis, C.D and Uthus, E.O. DNA Methylation, Cancer Susceptibility and Nutrient Interactions. Exp Biol Med November 2004 vol. 229 no. 10, 988-995

[13] Khan, S.I. et al (2012). Epigenetic Events Associated with Breast Cancer and Their Prevention by Dietary Components Targeting the Epigenome. Chem. Res. Toxicol. 2012, 25, 61–73

[14] Liu, L. Et al. Aging, cancer and nutrition: the DNA methylation connection. Mechanisms of Ageing and Development Volume 124, Issues 10–12, December 2003, Pages 989–998

[15] Su, L.J. et al.  Epigenetic contributions to the relationship between cancer and dietary intake of nutrients, bioactive food components, and environmental toxicants. Frontiers in Genetics, Vol 2, Article 91, 1-12,, 09 January 2012 | doi: 10.3389/fgene.2011.00091

[16] World Cancer Research Organisation. 2nd Expert Report: Food, Nutrition, Physical Activity and the Prevention of Cancer: A Global Perspective. Washington DC: AICR, 2007.

[17] Kim Y.-I.  Folate and DNA methylation: a mechanistic link between folate deficiency and colorectal cancer? Cancer Epidemiol Biomarkers Prev 13:511–519, 2004.

[18] Smith-Warner, S.A. et al.  Alcohol and breast cancer in women.  A pooled analysis of cohort studies.  JAMA 279 (1998), 535-540.

[19] van Engeland M, Weijenberg MP, Roemen GM, Brink M, de Bruine AP, Goldbohm RA, van den Brandt PA, Baylin SB, de Goeij AF, Herman JG. Effects of dietary folate and alcohol intake on promoter methylation in sporadic colorectal cancer: the Netherlands cohort study on diet and cancer. Cancer Res 63:3133–3137, 2003

[20] Choi SW, Stickel F, Baik HW, Kim YI, Seitz HK, Mason JB. Chronic alcohol consumption induces genomic but not p53-specific DNA hypomethylation in rat colon. J Nutr 129:1945–1950, 1999.

[21] Ross SA, Dwyer J, Umar A et al. (2008) Diet, epigenetic events and cancer prevention. Nutr Rev 66 (Suppl. 1), S1–S6.

[22] Fang MZ, Wang Y, Ai N, Hou Z, Sun Y, Lu H, Welsh W, Yang CS. Tea polyphenol (-)-epigallocatechin-3-gallate inhibits DNA methyltransferase and reactivates methylation-silenced genes in cancer celllines. Cancer Res 63:7563–7570, 2003.

[23] Meeran, S. M., Ahmed, A., and Tollefsbol, T. O. (2010) Epigenetic targets of bioactive dietary components for cancer prevention and therapy. Clin. Epigenetics 1, 101–116.

[24] Lee, W. J., and Zhu, B. T. (2006) Inhibition of DNA methylation by caffeic acid and chlorogenic acid, two common catechol-containing coffee polyphenols. Carcinogenesis 27, 269–277.

Whoppers in the NHS

Burger King Southampton General Hospital

Burger King, Level C, Southampton General Hospital

I locked my car and headed down the steps of the car park towards the main entrance of Southampton General Hospital.

Waves of anxiety swept over me.

I had come to visit a dear friend who is very poorly and I wasn’t sure what to expect.

Over the last two weeks things had taken a turn for the worse.

What could I say?  What should I say?

I just didn’t know.

My heart was heavy as I approached the main hospital building.

southampton gh

An ambulance raced past, siren blaring, blue lights flashing.

Glancing round I noticed people in pyjamas sitting on benches in the paved area opposite the entrance.

My nostrils twitched and involuntarily I held my breath; the warm air was thick with the stench of cigarette smoke.

Stubbing out her fag, a woman with long greasy hair, a pink dressing gown and fluffy slippers, grabbed her drip stand and shuffled across the zebra crossing and through the sliding door into the hospital.

I followed.

Inside, as my eyes adjusted to the light, I searched for signs. Costa Coffee. Reception. Hospital Security. Claims Solicitors. Outpatients.  Childrens Outpatients. Neurosciences. Emergency Department. X-Ray. Oncology. Burger King.

Burger King?

I walked closer.

Burger King?

Two kind faces watched as I approached.

“Do you need any help?” asked one with a friendly smile – hospital volunteers on ‘meet and greet’ duty.  The smile was genuine and I remembered to breathe properly again.

“I’m looking for Ward C4, but first I need a toilet, a cash point and a cup of tea”.

They gave me directions and another reassuring smile.

All around me were reminders of the frailty of the human body, my own frailty. Wheelchairs, walking sticks, grey faces, worry. Fear gripped me again.

Taking a deep breath, I pressed the buzzer for entry to the ward.

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Several hours later I emerged from the hushed efficiency of the clinical suites, a little more relaxed than I had entered.

I wished with all my heart that everything was back to normal.  But it wasn’t.  Nevertheless, there was no doubt about it – my friend was receiving the best possible medical, nursing and personal care.  The ward was spotlessly clean and every member of staff I had met, from the tea lady to the Consultant, had behaved with kindness, compassion and professionalism.

There is so much to be proud of in the NHS.

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Back outside, a queue was forming at Burger King.

Furtively, I pulled my iPhone out of my pocket and took a picture.  I had to convince myself that I hadn’t imagined it, that the cortisol coursing through my veins hadn’t scrambled my senses.

But there it was – plain to see – Home of the Whopper.

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University Hospital Southampton NHS Foundation Trust is, according to its annual report:

…a centre of excellence for training the doctors and nurses of the future and developing treatments for tomorrow’s patients. Its role in research and education, developed in active partnership with the University of Southampton distinguish it as a hospital that works at the leading edge of healthcare developments in the NHS and internationally.

I believe them.  But given these credentials, surely they must know that diet is a key determinant of long-term health?

Reports by the World Health Organisation describe in detail how, in most countries, a few major risk factors account for much of the illness and death (1).

For non-communicable diseases, the most important risks include high blood pressure, high concentrations of cholesterol in the blood, inadequate intake of fruit and vegetables, overweight or obesity, physical inactivity and tobacco use.

These risks arise predominantly from elevated consumption of energy-dense, nutrient-poor foods that are high in fat, sugar and salt; reduced levels of physical activity at school, work, and home; and smoking.

There, in front of my eyes, was evidence that one of the most prestigious teaching hospitals in the UK is not only ignoring public health research, it is encouraging its patients, carers and staff to indulge in food and drink that is scientifically proven to damage human health.

At this point, I must stress that NHS patients are not given fast food by hospital staff when they are on the ward.  They are offered three meals a day, with choices from an extensive menu of hot and cold dishes.  My friend had eaten a Cornish pasty followed by a yoghurt, for example.

This food is not, however, available for visitors or staff.  Furthermore, as I had witnessed myself, patients are able to leave the wards during the day and wander around the shopping area.  Outside, I had seen some of them eating burgers whilst smoking.

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Two weeks ago, a Health and Wellbeing Summit was convened by NHS Employers and Dame Carol Black.  It brought together a range of senior NHS leaders to demonstrate their commitment to the health and wellbeing of the NHS workforce.

The Boorman Review published in 2009 had already highlighted both the individual and business value of healthier NHS employees.

Steve Boorman concluded:

We believe that the NHS can reduce current rates of sickness absence by a third, and doing so would mean:

  • 3.4 million additional available working days a year for NHS staff

  • equivalent to an extra 14,900 whole-time equivalent staff

  • with an estimated annual direct cost saving of £555 million

At the NHS Employers Summit, Dame Carol Black said:

The benefits of strong health and wellbeing programmes in the NHS go far beyond the individual. Staff whose wellbeing and health is well supported deliver better care and are more resilient and better engaged with their role. At a time when the NHS is striving to make the absolute most of its resources, getting this right is crucial. I am very pleased that the NHS leaders in the new system are getting behind this agenda so quickly.

Participants signed a pledge to continue to improve the health and wellbeing of staff who work in healthcare.


We will:

  • foster a culture that promotes better physical and mental health and wellbeing for staff in all workplaces used by our organisation
  • work to strengthen staff engagement both in and through these endeavours
  • include measures of employee health and wellbeing within Key Performance Indicators and other performance monitoring systems within our organisation
  • sign up to the relevant parts of the Public Health Responsibility Deal for our staff
  • exploit the relationships we have with other NHS organisations, sharing expertise and experience in ways of safeguarding and improving staff health and wellbeing

Where does Burger King in a hospital fit into this, I wonder?

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America has the same problem but the tide is turning.

After 34 years at the Children’s Hospital of Philadelphia, McDonald’s closed its doors last September.

But as fast as some hospitals are ending contracts with fast food outlets, others are starting them.  Chick-fil-A recently set up shop in several facilities, including the Texas Medical Center’s St. Luke’s Episcopal Hospital and the Medical University of South Carolina University Hospital in Charleston, S.C.

Of the 14,000 McDonald’s in the United States, the company says there are 27 in hospitals.  They say that fast food outlets can be a convenience and a comfort for patients. The food may also appeal to some patients’ picky tastes when undergoing difficult treatments.


The Physicians’ Committee for Responsible Medicine surveyed hospital food at 100 US hospitals in 2011.  Some had as many as five fast food outlets.

Many clinicians feel that the presence of such outlets sends an inconsistent message to patients, staff and the community and have campaigned to remove them.  It has not always been easy.

Ten years ago, the Cleveland Clinic in Ohio tried in vain to terminate its contract with McDonald’s.  At the time, the clinic’s lead heart surgeon (and now hospital CEO), Delos Cosgove, proposed removing all fast food vendors.

The Pizza Hut did close. But McDonald’s stayed and remains a tricky relationship for the hospital, which is a pioneer in whole environment approaches to employee wellness.

Despite their failure to eliminate McDonald’s from their campus, the Cleveland Clinic, which has 37,000 employees, pressed ahead with other actions focused on the four big public health issues: tobacco, food choices and portion size, physical inactivity and stress.

Here is their timeline:

  • July 2005: Designated all Cleveland Clinic campuses smoke-free
  • January 2007: Offered free smoking cessation services to all Cuyahoga County residents for six months
  • February 2007: Banned trans-fats from all public and patient menus
  • May 2007: Began converting vending machines to replace unhealthy food items with healthy snack choices
  • September 2007: Stopped hiring smokers
  • November 2007: Created the country’s first Chief Wellness Officer position, with the appointment of Michael F. Roizen, MD
  • January 2008: Established the Wellness Institute
  • May 2008: Began free yoga classes for employees
  • July 2008: Launched weekly farmers market for employees and community
  • August 2008: Implemented free Weight Watchers services for EHP member employees
  • October 2008: Welcomed first class of Lifestyle 180 participants, a lifestyle modification program for patients with chronic conditions like high blood pressure, diabetes, and heart disease
  • November 2008: Initiated free memberships to Curves and Cleveland Clinic-owned fitness centers for EHP member employees
  • January 2009: Rolled out GO Foods healthy labeling in all Cleveland Clinic cafeterias – GO foods contain nothing that can harm your body.
  • August 2010: Banned sugared beverages from all cafeterias and vending machines

What are the results?

  1. Over 10 years, their no-smoking policy and programme has achieved a 6 to 1 return on investment, reducing the percentage of smokers to 2.1%
  2. US$36 million has been saved from smoking quitters
  3. US$114 million has been saved from not hiring smokers
  4. It is difficult to quantify savings from avoiding second-hand smoking, but it could be as much as the above, says Michael Roizen MD, Chief Wellness Officer
  5. Since 2008, nearly 300,000 lbs. have been lost by Cleveland Clinic employees.  It is estimated that this equates to US$14-15 million in healthcare cost savings.
  6. Memberships and visits at Cleveland Clinic-owned fitness centers have increased by 358%, with total visits now averaging over 20,000 per month.
  7. Registration for Sunrise/Sunset Yoga continues to grow with nearly 50 classes and 3,300 registered participants in 2011.
  8. Since 2009, more than 30,000 unique employees have enrolled in Shape Up and GO!

Dr Michael Roizen MD, Head of the Cleveland Clinic Wellness Institute, says:

Emotions and facts cannot change people’s behaviour.  But changing the environment can.  Organisations need to change the environment so that it is easy to do healthy things and hard to do unhealthy things.

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This is easy to say but hard to do.

I wouldn’t mind betting that the Board responsible for Southampton General Hospital is facing a similar dilemma to that of Croydon University Hospital Trust in Surrey, which received negative media coverage when they had to pay £24,000 to shut down a Burger King restaurant inside their hospital.

£24,000 is enough to cover the salary of a low-grade nurse for a year

bleated the Daily Mail, without considering the long-term costs to the health service of people consuming Burger King’s products.

It may also be the case that they do not have direct control over which businesses operate in the entrance area if this is handled by a landlord.

At some point, however, someone within the NHS needs to demonstrate leadership, courage and imagination and set about creating hospital environments which make it easy for people to make healthy choices, as they have done at the Cleveland Clinic in the USA.

Will Southampton General Hospital, excellent in so many ways, take up the challenge?  I hope so.

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  1. World Health Report 2002. Reducing risks, promoting healthy life. Geneva, World Health Organization, 2002.

An idealist is one who, on noticing that a rose smells better than a cabbage, concludes that it will also make better soup

cabbage and rose 3686x1323

I came across this little poem the other day:

I wonder if the cabbage knows

He is less lovely than the Rose;

Or does he squat in smug content,

A source of noble nourishment;

Or if he pities for her sins

The Rose who has no vitamins;

Or if the one thing his green heart knows

That self-same fire that warms the Rose?

This made me think.

Is it true that the rose has no vitamins?

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The Chinese were the first to experiment with flowers as food and their many and varied recipes can be traced back as far back as 3,000 B.C.

In Roman times, the edible flowers of pinks, violets and roses were used in dishes, and lavender in sauces.

Gardeners and cooks over 1000 years ago were already using pot marigolds and orange blossom in their cooking and edible flowers were especially popular in the Victorian era.

After falling out of favour for many years, flower cookery is now back in vogue.

Innovative chefs in fancy restaurants have taken to garnishing their entrees with flower blossoms for a touch of elegance.

But do flowers only have aesthetic value in cooking?

Or do they have nutritive value too?

broccoli flowering

Broccoli flowering

Of course, this is a bit of a trick question because we are already familiar with eating flower heads.

Broccoli and cauliflower are good examples and we know that they are packed with vitamins, minerals and other beneficial substances which act as antioxidants.

But what about the sort of flowers which are usually grown for ornamental purposes, like roses and pansies?

Chive and viola flower salad (

Chive and viola flower salad (

Nutrient content of edible flowers

I have searched high and low in the scientific literature for quantitative data on the nutrient content of flower petals. There are relatively few references, particularly in English.

Most of the literature is focused on evaluating flowers for their sensory characteristics, such as appeal, size, shape, colour, taste, and above all, aroma, which is important for the cosmetic and perfume industry.

The references I have found in journals from researchers in Turkey, Bosnia, Poland, South Korea and China among others, suggest that the common components – proteins, fats and carbohydrates – are present in similar amounts to those in other plant organs, e.g., in leaf vegetables (1).

Available data on a number of edible flowers show that petals also contain an array of vitamins and minerals, particularly vitamins A and C, various B vitamins, folic acid, and minerals including calcium, magnesium, potassium, iron and phosphorus.

The data in this table were compiled from sources in the list of references below (1-7).








Vit A




Vit C















Chives 3.07 108.5
Pumpkin 1.03 3.28 0.07 1947 59 28 39 0.7 24 173
Sesbania 1.28 6.73 0.04 0 102 73 19 0.84 12 184
Hawthorn 900
Banana 2.07 91.4 0.4 33 43 34 571
Gourd 0.62 3.39 0.02 16 6 10.1 26 0.2 11 150
Broccoli 2.98 5.24 0.35 150 71 93.2 48 0.88 25 325

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Flower colour is determined by many chemical compounds but carotenoids and flavonoids are the most important.  The flavonoids in particular have been shown to give flowers high antioxidant capacity (1).

Dandelions, for example, contain numerous flavonoids and carotenoids with antioxidant properties, including four times the beta carotene of broccoli, as well as lutein, cryptoxanthin and zeaxanthin. They are also a rich source of vitamins, including folic acid, riboflavin, pyroxidine, niacin, and vitamins E and C.


Violets contain rutin, a phytochemical with antioxidant and anti-inflammatory properties that may help strengthen capillary walls.

Rose petals contain bioflavonoids and antioxidants, as well as vitamins A, B3, C and E (6,7).

Nasturtiums contain cancer-fighting lycopene and lutein, a carotenoid found in vegetables and fruits that is important for vision health.

Lavender contains vitamin A, calcium and iron, and is said to benefit your central nervous system.

Chive blossoms contain vitamin C, iron and sulphur, as well as many antioxidants, and have traditionally been used to help support healthy blood pressure levels.

edible flowers 3

So, to answer my original question – yes – roses and other flowers do contain vitamins.

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Practical considerations

When collecting flowers for eating, keep the following in mind;

  • Accurate identification of flowers is essential – if you are in doubt, DO NOT EAT
  • Pick young flowers and buds on dry mornings, before the sun becomes too strong, so the colour and flavours will be intense
  • Use flowers immediately for best results or refrigerate in a plastic bag for a couple of days. Dried or frozen flowers are best used in infusions or cooked
  • Generally, only the petals are used, so discard stamens, pistil and calyx of large flowers like hollyhocks, roses, lilies and hibiscus. The bitter ‘heel’ at the base of the petal should be removed
  • Petals of daisies, borage and primroses can easily be separated from the calyx
  • Smaller flowers in umbels like fennel and dill can be cut off and used whole

There are some poisonous flowers you definitely cannot eat, for example, daphne, foxglove, daffodils, hyacinths and all members of the nightshade family. Consult a reference book, or ask an expert in this area, before being too adventurous.  If you are not sure, DO NOT EAT.  I have included a list of books on edible and poisonous flowers below.

Edible ornamental flowers

Many garden favourites are edible and a few are listed below:-

  • Alpine pinks (Dianthus) – a clove-like flavour ideal for adding to cakes as flavoured sugar, oils and vinegars
  • Bergamot (Monardia didyma) – a strong spicy scent, makes good tea and complements rice and pasta
  • Chrysanthemum (Chrysanthemum) – petals flavour and colour cream soups, fish chowder and egg dishes in the same way as calendula
  • Daisy (Bellis perennis) – not a strong flavour but petals make an interesting garnish for cakes and salads
  • Day lily (Hemerocallis) – add buds and flowers to stir fry, salads and soups. Crunchy with a peppery after taste but may have a laxative effect. Avoid buds damaged by gall midge
  • Elderflower (Sambucus nigra) – used to make wine and cordials, or place in a muslin bag to flavour tarts and jellies but removed before serving. Elderflowers can be dipped in batter and deep fried
  • Hibiscus (H. rosa-sinensis) – refreshing citrus-flavoured tea enhanced by rosemary
  • Hollyhock (Alcea rosea) – remove all traces of pollen and decorate cakes with crystallized petals
  • Lavender (Lavandula augustifolia) – flavoured sugar, honey or vinegar can be used in cakes and biscuits and dried flowers used as tea
  • Nasturtium (Tropaeolum majus) – brightly-coloured, peppery flowers are good in salads and pasta dishes. The whole flower, leaves, and buds can be used or just the petals for a milder flavour
  • Pot marigold (Calendula officinalis) – intense colour and a peppery taste useful in soups, stews and puddings. Petals can be dried or pickled in vinegar or added to oil
  • Primrose (Primula vulgaris) – decorate cakes with crystallized or fresh primrose or cowslip flowers. They can be frozen in ice cubes
  • Rose (Rosa) – all roses are edible with the more fragrant roses being the best. Petals can be crystallized, used to flavour drinks, sugar and even icing for summer cakes
  • Scented geraniums (Pelagonium) – flowers are milder than leaves and can be crystallized or frozen in ice cubes for summer cordials
  • Sunflower (Helianthus annuus) – blanch whole buds and serve with garlic. Petals can be used in salads or stir fries
  • Sweet violet (Viola odorata) – delicate flavour suitable for sweet or savoury dishes as well as tea. Use candy violets and pansies as a garnish on cakes and soufflés
  • Tiger lily (Lilium leucanthemum var. tigrinum) – delicate fragrance and flavour enhances salads, plus can be used to stuff fish

Edible flowers from your vegetable patch and herb garden

Herb flowers like basil, chives, lavender, mint, rosemary and thyme impart a more subtle flavour to food than the leaves. By adding sprigs of edible herb flowers like basil or marjoram to oils the delicate flavours can be used over a longer period.

  • Borage (Borago officinalis) – the cucumber flavour of these attractive blue flowers adds interest to cakes, salads and pate. Flowers are easily removed and can be frozen in ice cubes or crystallized
  • Basil (Ocimum basilicum) – sweet, clover-like flavour compliments tomato dishes as well as oils, salad dressings and soups. Use aromatic leaves of both green and purple in Mediterranean dishes
  • Dill (Anethum graveolens) – aniseed flavour, ideal addition to salads, vegetables and fish dishes. Add flowers to mayonnaise, white sauce and pickles
  • Chives (Allium schoenoprasum) – mild onion flavour, good in salads, egg dishes and sauces for fish
  • Clover (Trifolium pratense) – both red and white clover flowers can be used to garnish fruit and green salads or make wine from whole red flowers
  • Courgette or marrow flowers – can be eaten hot in a tomato sauce or cold stuffed with cooked rice, vegetables and nuts. Use male flowers so as not to reduce yield
  • Fennel (Foeniculum vulgare) – all parts are edible and enhance salmon, pâtés and salads. Flowers preserved in oil or vinegar can be used in winter
  • Garden pea (Pisum sativum) – add flowers and young shoots to salad for a fresh pea taste
  • Mint (Mentha sp) – Apple, pineapple and ginger mint, plus peppermint and spearmint flowers can all be used in oil and vinegar for both sweet and savoury dishes
  • Rosemary (Rosmarinus officinalis) – a sweet flavour similar to the leaves can be used fresh to garnish salads and tomato dishes or to flavour oil
  • Salad rocket or arugula (Eruca vescaria) – adds sharp flavour to salads or preserve in oil

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Here is a recipe using nasturtium flowers from one of my favourite cookery books – “Purple Citrus and Sweet Perfume” by Silvena Rowe.  Although not all of the recipes are plant-based, I love Silvena Rowe’s creative combinations of flavours and colours.

Pink Grapefruit, Avocado and Pomegranate Salad with Nasturtium Flowers

Serves 4

pink grapefruit avocado and pomegranate salad with nasturtium flowers


  • 2 pink grapefruits
  • 2 large avocados, stones removed, peeled and sliced into thin wedges
  • 1/2 large bunch of fresh purple basil, leaves only
  • seeds of 1 large pomegranate
  • 3 tablespoons white wine vinegar
  • 4 tablespoons olive oil
  • 1 teaspoon mild mustard
  • 1 teaspoon pomegranate molasses
  • 1 teaspoon ground sumac
  • 6-8 nasturtium flowers


Peel the pink grapefruits, making sure you cut away all the pith, then cut them into individual segments. Place in a large bowl along with any juice, add the avocado, basil and pomegranate seeds, and season. Whisk together the vinegar, olive oil, mustard and pomegranate molasses and pour over the salad. Toss gently to combine, sprinkle with the sumac and serve garnished with the nasturtium flowers.

Books on poisonous and edible flowers

  • Poisonous Plants by Elizabeth A. Dauncey
  • The Edible Flower Garden by Kathy Brown
  • Edible flowers by Kathy Brown
  • The Edible Flower Garden by Rosalind Creasy
  • Cooking with Edible Flowers by Miriam Jacobs
  • Good Enough to Eat by Jekka McVicar
  • Edible Flowers, Desserts & Drinks by Cathy Wilkinson Barash
  • Edible Flowers from Garden to Palate by Cathy Wilkinson Barash


  1. Otakar Rop, Jiri Mlcek, Tunde Jurikova, Jarmila Neugebauerova and Jindriska Vabkova. Edible Flowers — A New Promising Source of Mineral Elements in Human Nutrition. Molecules 2012, 17, 6672-6683; doi:10.3390/molecules17066672
  2. Monika Grzeszczuk, Aneta Wesołowska, Dorota Jadczak, Barbara Jakubowska.  NUTRITIONAL VALUE OF CHIVE EDIBLE FLOWERS. Acta Sci. Pol., Hortorum Cultus 10(2) 2011, 85-94
  3. USDA National Nutrient Database.
  4. Azra Tahirović, Amira Čopra – Janićijević, Nedžad Bašić, Lela Klepo, Mirel Subašić1. DETERMINATION OF VITAMIN C IN FLOWERS OF SOME BOSNIAN CRATAEGUS L. SPECIES. Works of the Faculty of Forestry University of Sarajevo No. 2, 2012 (1-12)
  5. Zhan-Wu Sheng, Wei-Hong Ma, Zhi-Qiang Jin1, Yang Bi, Zhi-Gao Sun, Hua-Ting Dou, Jin-He Gao, Jing-Yang Li and Li-Na Han.  Investigation of dietary fiber, protein, vitamin E and other nutritional compounds of banana flower of two cultivars grown in China.  African Journal of Biotechnology Vol. 9(25), pp. 3888-3895, 21 June, 2010
  6. Alejandra Mabellinia, Elisabeth Ohacoa, Mónica Roselva Ochoaa, Alicia Graciela Kesselera, Carlos Alberto Márqueza, Antonio De Michelisb. Chemical and Physical Characteristics of Several Wild Rose Species Used as Food or Food Ingredient. Int. J. Ind. Chem., Vol. 2, No. 3, 2011, pp. 158-171
  7. Hanan M. K. E. Youssef, Rasha M. A. Mousa. Nutritional Assessment of Low-Calorie Baladi Rose Petals Jam. Food and Public Health 2012, 2(6): 197-201. DOI: 10.5923/j.fph.20120206.03

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On chlorophyll extracts, green poo and hogwash

“It will probably give her green poo” said Eric.

Eric had just received an email from his physiotherapist, worried about a friend with Lyme disease who had been told to take chloroxygen.

Realising this was outside his area of expertise, Eric contacted me. We have known each other for a long time.

Chloroxygen? For Lyme disease? Really?

Now I was curious.

Is there something in this or is it just another load of internet promoted hogwash?

So I decided to investigate the scientific literature on chloroxygen and its effect on health, particularly Lyme disease.

What is chloroxygen?

According to the promotional literature of one well-known brand, chloroxygen is an extract of chlorophyll from stinging nettles, suspended in water and glycerine, and free from preservatives and alcohol (1).


This seemed odd to me because the chlorophyll molecule has an oil-loving tail and does not dissolve in water.

I examined the label: Chlorophyll (Sodium Copper Chlorophyllins) 50mg per serving.

Just as I thought.

Chlorophyllin is a semi-synthetic mixture of sodium copper salts derived from chlorophyll. Chlorophyll is chemically treated and the magnesium atom at the centre of the ring is replaced with copper and the oil-loving tail is lost.

Unlike natural chlorophyll, chlorophyllin is water-soluble.

Although the content of different chlorophyllin mixtures may vary, two compounds commonly found in commercial chlorophyllin mixtures are trisodium copper chlorin e6 and disodium copper chlorin e4 (2).

These chlorophyllins are not naturally occurring substances and it is therefore more accurate to describe chloroxygen as a semi-synthetic chlorophyll derivative.

Health benefits claimed for chlorophyll-derived products

As you can see from the picture above, there are some, shall we say ‘interesting’ claims for the health benefits of chlorophyll-derived products, including but not limited to:

  1. Anti-bacterial activity
  2. Enhancement of the oxygen carrying capacity of the blood by building red blood cells, which boosts energy levels and facilitates high altitude acclimation
  3. Deodorant for bodily smells
  4. Inhibition of toxins that damage the body

How many of these are supported by scientific evidence, I wondered.

1.  Anti-bacterial activity

Most claims that chlorophyll products can kill bacteria are based on research performed early in the 20th century, before antibiotics were available to fight infections (3). Although many of these studies do not meet the rigorous standards of modern science, there is evidence that chlorophyll can kill certain types of bacteria (4). There is, however, no published evidence that chlorophyll can kill the type of bacteria which cause Lyme disease (more on this below).

Even if there were such evidence, it is unlikely to be a practical choice, because very high chlorophyll concentrations are needed for any positive anti-bacterial effect and modern antibiotics are far more effective.

2.  Increase in the oxygen carrying capacity of blood

Marketing brochures for chloroxygen claim that chlorophyll is the “blood of plants” and “increases haemoglobin’s ability to grab and hold oxygen” (1).

Chloroxygen 2

It is true that the chemical structures of haemoglobin and chlorophyll display some similarities but they perform entirely different functions in living organisms and are made via different pathways (5).  One of my friends who is a chemist gets very annoyed about this.  He says that claiming that chlorophyll and haemoglobin are closely related is like saying that a man is like a woman.

Haemoglobin is a molecule in the red blood cells of animals, made from a red iron-containing pigment called haem, bound to a protein, globin. Its primary function is to transport oxygen from the lungs to the tissues and then to transport carbon dioxide back from the tissues to the lungs.

Chlorophylls are a group of magnesium-containing molecules in the chloroplasts of plant cells. Their role is to trap energy from sunlight. This energy is then used, together with carbon dioxide, to manufacture the carbohydrates that all living organisms use as food.

Chlorophyll-a, the most abundant and most important chlorophyll of the family, represents about 75 per cent of the green pigments in plants. It is very susceptible to metabolism in the human gut and little of the chlorophyll-a that is ingested emerges intact (6).

Chlorophyll does not bind or transport oxygen and is not absorbed into the bloodstream. It is therefore biologically implausible that it “increases haemoglobin’s ability to grab and hold oxygen”.

Despite an exhaustive search of the scientific literature, I have been unable to find any evidence that the effect of chlorophyll on oxygen carrying capacity in humans has ever been studied.

3.  Deodorant for bodily smells

In the 1940’s and 1950’s various claims were made for the deodorant properties of chlorophyll. It was alleged to reduce bad breath, stench from skin ulcers, vaginal odours and bad smells from colostomies. Studies published in the British Medical Journal in 1953 provided no evidence to support these claims (7). According to John C. Kephart, who performed studies at the laboratories of the National Chlorophyll and Chemical Company about 20 years ago, “No deodorant effect can possibly occur from the quantities of chlorophyll put in products such as gum, foot powder, cough drops, etc. To be effective, large doses must be given internally” (8).

chlorophyll deodorant

The Food and Drug Administration of the United States published a monograph pertaining to the use of chlorophyllin copper complex as a drug entitled “Deodorant Drug Products for Internal Use.” This monograph describes chlorophyllin copper complex as “generally recognized as safe and effective”, and describes the following uses: (i) “An aid to reduce odor from a colostomy or ileostomy.” (ii) “An aid to reduce fecal odor due to incontinence” (9).

4.  Inhibits toxins that damage the body

Chlorophyll and chlorophyllin are able to form tight molecular complexes with certain chemicals known or suspected to cause cancer, including polycyclic aromatic hydrocarbons found in tobacco smoke (10), some heterocyclic amines found in cooked meat (11), and aflatoxin-B1 (12).

Diets high in red meat and low in green vegetables are associated with an increased risk of colon cancer. It has been suggested that haem, the iron carrier of red meat, is involved in diet-induced damage to the cells of the colon resulting in cancer. There is evidence that natural chlorophyll, rather than chlorophyllin, reduces the toxicity caused by haem (13).

Researchers at Oregon State University reported that chlorophyll and its derivative chlorophyllin are effective in limiting the absorption of aflatoxin in humans (14). Aflatoxin is produced by a fungus that is a contaminant of grains including corn, peanuts and soybeans; it is known to cause liver cancer – and can work in concert with other health concerns, such as hepatitis.



Studies in animal models have suggested that chlorophyllin may act as an antioxidant (15) but more research is needed to understand the bioavailability and metabolism of natural chlorophylls and synthetic chlorophyllin in humans before conclusions can be drawn (16).

What is Lyme disease?

Lyme disease is a tick-borne infection caused by an organism called Borrelia burgdorferi. This is a type of gram-negative bacterium called a spirochete. Spirochetes look like miniature springs and move in a corkscrew fashion, which enables them to travel more easily through viscous substances like mucus.

Borrelia burgdorferi

Borrelia burgdorferi

The earliest and most common symptom of Lyme disease is a pink or red circular rash that develops around the area of the bite, three to 30 days after someone is bitten. The rash is often described as looking like a bull’s-eye on a dart board.

Early symptoms of Lyme disease

Early symptoms of Lyme disease

You may also experience flu-like symptoms, such as tiredness, headaches and muscle or joint pain.

If Lyme disease is left untreated, further symptoms may develop months or even years later and can include:

  • muscle pain
  • joint pain and swelling of the joints
  • neurological symptoms, such as temporary paralysis of the facial muscles

Lyme disease in its late stages can trigger symptoms similar to those of fibromyalgia or chronic fatigue syndrome. This is known as chronic Lyme disease. More research into this form of Lyme disease is needed (17).

A person with Lyme disease is not contagious because the infection can only be spread by ticks.

As the causal organism is a bacterium, Lyme disease is medically treated with antibiotics.

Choice of antibiotic varies with stage of the disease but amoxicillin, doxycycline and ceftriaxone are commonly used (18). Treatment is usually required for 2 to 4 weeks.

In the early stages, oral antibiotics are usually effective but if treatment is delayed until later stages, then intravenous antibiotics may be required.


Whilst there is strong scientific evidence that consumption of green leafy plants, rich in chlorophyll and many other nutrients, is beneficial for human health (19) (20) (21), there is limited scientific evidence to substantiate the health claims made for semi-synthetic chlorophyll-derived products such as chloroxygen.

Chlorophyll and its semi-synthetic chlorophyllin derivatives may have some weak anti-bacterial activity, but there is absolutely no scientific evidence for their efficacy against the bacterium which causes Lyme disease.

Furthermore, there is no plausible biological explanation or evidence to support the claim that chloroxygen increases the oxygen carrying capacity of the blood.

This is utter hogwash.

Many of the nutrients which build and sustain the essential elements in blood are found in plant foods high in chlorophyll, but this is the limit of the association between chlorophyll and the oxygen carrying capacity of blood.

Drinking green juices and eating green vegetables such as rocket (arugula), broccoli, parsley, kale and spinach, together with other plant foods rich in iron and other minerals, such as pulses and sea vegetables (these are actually algae rather than plants), is likely to be just as effective for strengthening the blood, and maybe more so, than taking supplements of man-made chemical derivatives of chlorophyll.


There is evidence that chlorophyll and chlorophyllin can bind to toxic substances such as aflatoxin and may prevent cancer and other damage to the body. The anti-cancer properties of whole plants are, however, well-documented (22) and the studies reported on chlorophyll products may simply offer potential mechanisms for some of the benefits of eating a plant-based diet.

So my advice to Dave and his friends is not to take promotional literature on dietary supplements at face value.  In some cases, there is little or no evidence to substantiate the claims made for the products.

Consuming a predominantly plant-based diet will help to support the immune system in fighting infections and improve general health, but if Lyme Disease is diagnosed, it is important to seek medical treatment with modern antibiotics.

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1. Chloroxygen. [Online]
2. Chlorophyll: Structural Properties, Health Benefits and Its Occurrence in Virgin Olive Oils. İnanç, A. Levent. 2011, Akademik Gıda/Academic Food Journal, Vol. 9 (2), pp. 26-32.
3. PhD, James A. Lowell. Amazing claims for chlorophyll (1987). Quackwatch. [Online]
4. Anti-bacterial activity of chorophyll. Mowbray, Sheila. 2 February 1957, British Medical Journal, Vol. 1(5013), pp. 268-270.
5. Haems and chlorophylls: comparison of function and formation. Hendry, G.A.F. and Jones, O.T.G. 1980, Journal of Medical Genetics, Vol. 17, pp. 1-14.
6. The metabolites of dietary chlorophyll. Ma, L. and Dolphin, D. 1999, Phytochemistry, Vol. 50, pp. 195-202.
7. Assessment of chlorophyll as a deodorant. Brocklehurst, J.C. 7 March 1953, British Medical Journal, Vol. 1(4809), pp. 541-544.
8. Chlorophyll derivatives: their chemistry, commercial preparation and uses. Kephart, J.C. 1955, Journal of Ecological Botany 9:3, Vol. 9, pp. 3-38.
9. Federal Register Volume 55 No. 92 – Chlorophyllin as Deodorant. Food and Drug Administration [Online] 11 May 1990.
10. Mechanisms of the in vitro antimutagenic action of chlorophyllin against benzo[a]pyrene: studies of enzyme inhibition, molecular complex formation and degradation of the ultimate carcinogen. Tachino N, Guo D, Dashwood WM, Yamane S, Larsen R, Dashwood R. 1994, Mutation Research , Vol. 308 (2), pp. 191-203.
11. Study of the forces of stabilizing complexes between chlorophylls and heterocyclic amine mutagens. Dashwood R, Yamane S, Larsen R. 1996, Environ Mol Mutagen, Vol. 27 (3), pp. 211-218.
12. Mechanisms of chlorophyllin anticarcinogenesis against aflatoxin B1: complex formation with the carcinogen. Breinholt V, Schimerlik M, Dashwood R, Bailey G. 1995, Chem Res Toxicol., Vol. 8 (4), pp. 506-514.
13. Natural chlorophyll but not chlorophyllin prevents heme-induced cytotoxic and hyperproliferative effects in rat colon. de Vogel J, Jonker-Termont DS, Katan MB, van der Meer R. 2005, Journal of Nutrition, Vol. 135 (8), pp. 1995-2000.
14. Effects of Chlorophyll and Chlorophyllin on Low-Dose Aflatoxin B1 pharmacokinetics in human volunteers. Carole Jubert, John Mata, Graham Bench, Roderick Dashwood, Cliff Pereira, William Tracewell. December 2009, Cancer Prev Res 2009;2(12) December 2009, Vol. 2 , pp. 1015-1022.
15. Effect of chlorophyllin against oxidative stress in splenic lymphocytes in vitro and in vivo. Kumar SS, Shankar B, Sainis KB. 2004, Biochim Biophys Acta., Vol. 1672 (2), pp. 100-111.
16. Bioavailability of dietary sodium copper chlorophyllin and its effect on antioxidant defence parameters of Wistar rats. . Gomes, B. B., Barros, S. B., Andrade-Wartha, E. R., Silva, A. M., Silva, V. V. and Lanfer-Marquez, U. M. 2009, J. Sci. Food Agric., Vols. 889: 2003–2010, pp. 2003-2010.
17. Lyme disease. NHS Choices. [Online]
18. The Merck Manual of Diagnosis and Therapy. 19th. s.l. : Merck Manuals, 2011.
19. Global burden of disease study 2010. Murray, C. et al. 13 December 2012, The Lancet.
20. Campbell, T C and Campbell, T M. The China Study. s.l. : Benbella Books, 2006.
21. Adherence to the World Cancer Research Fund/American Institute for Cancer Research guidelines and risk of death in Europe: results from the European Prospective Investigation into Nutrition and Cancer cohort study. al, Anne-Claire Vergnaud et. 3 April 2013, American Journal of Clinical Nutrition.
22. World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. Washington DC : AICR, 2007.

How to prevent cancer

Vegetables and FruitsSix years ago the World Cancer Research Fund and the American Institute of Cancer Research published the mother of all literature reviews on food, nutrition, physical activity and the prevention of cancer (1).

A panel of 21 world-renowned scientists reviewed the research evidence and drew conclusions based on in-depth analysis of over 7,000 scientific studies published on cancer prevention over the last 50 years.

As a result of this review they made a number of recommendations:

  1. Be as lean as possible without becoming underweight
  2. Be physically active for at least 30 minutes per day
  3. Limit consumption of energy-dense foods and avoid sugary drinks
  4. Eat more of a variety of vegetables, fruit, whole grains and pulses
  5. Limit consumption of red meats and avoid processed meats
  6. If consumed at all, limit alcoholic drinks to 2 per day for men and 1 per day for women
  7. Limit consumption of salty foods and foods processed with salt
  8. Don’t use supplements to protect against cancer
  9. Do not smoke or chew tobacco
  10. Breastfeed exclusively for up to 6 months and then add other liquids and foods
  11. After treatment, cancer survivors should follow the recommendations for cancer prevention.

Since then further research has been conducted to see whether compliance with these recommendations has any effect on the risk of death from cancer and other diseases.

The findings were published in the American Journal of Clinical Nutrition on 3 April 2013 (2).

Researchers investigated nearly 380,000 people in nine European countries over 12 years and examined their diet and lifestyle to see how closely they complied with seven of World Cancer Research Fund/American Institute for Cancer Research’s (WCRF/AICR) Recommendations for Cancer Prevention.

They found that the risk of dying from several diseases, including cancer, circulatory diseases and respiratory diseases, can be reduced by 34 per cent if these recommendations are followed.

Those who most closely followed the WCRF/AICR Recommendations had a 50 per cent reduced chance of dying from respiratory disease, 44 per cent for circulatory disease and 20 per cent for cancer, when compared to the group with the lowest level of compliance.

The Recommendations with the greatest impact on reducing the risk of death from disease were being as lean as possible without becoming underweight (22 per cent reduced risk) and eating mostly plant foods (21 per cent).

In terms of cancer, limiting alcohol consumption and following the plant food recommendation reduced the risk of dying from the disease by the greatest margin, at 21 per cent and 17 per cent respectively.

The study is the first to examine breastfeeding as part of a combination of lifestyle changes to see what effect it has on risk of dying.  It showed that women who breastfed for at least six months had a reduced risk of death from cancer (ten per cent) and circulatory disease (17 per cent).

Although the WRCF/AICR recommendations were focused on the prevention of cancer, this study shows that adherence to these recommendations also reduces the risk of other diseases.

The bottom line is that maintaining a lean body by consuming a predominantly plant-based diet, being physically active and minimising intake of alcohol is most likely to protect you from cancer.  Looking after yourself in this way will also help to reduce your risk of circulatory and respiratory diseases.

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1. World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. Washington DC : AICR, 2007.

2. Adherence to the World Cancer Research Fund/American Institute for Cancer Research guidelines and risk of death in Europe: results from the European Prospective Investigation into Nutrition and Cancer cohort study. Anne-Claire Vergnaud et al. 3 April 2013, American Journal of Clinical Nutrition.

Is salad really more dangerous than beefburgers?

bagged-lettuce-recall“Salad is more dangerous than beefburgers” claims a headline in yesterday’s Telegraph newspaper in London.


The facts are that earlier this week the Health Protection Agency confirmed that an investigation into an outbreak of Cryptosporidium infection that affected around 300 people in England and Scotland in May 2012 showed strong evidence of an association with eating pre-cut bagged salad products which are likely to have been labelled as ‘ready-to-eat’. The outbreak was short lived and the numbers of cases returned to expected seasonal levels within a month of the first cases being reported. Most of those affected had a mild to moderate form of illness and there were no deaths associated with the outbreak.

cryptosporidiumCryptosporidium is a microscopic protozoan parasite that causes an infection called cryptosporidiosis affecting people and cattle.  The most common symptom is watery diarrhoea, which can range from mild to severe.  There is a number of potential sources, including consumption of contaminated water or food, swimming in contaminated water or through contact with contaminated food or affected animals.

If you follow standard food safety advice to wash all fruits and vegetables, including salad, before you eat them, as well as washing your hands and using clean chopping boards, knives and other utensils, you will greatly reduce the risk of infection.


Is it true that salad is more dangerous than meat?

Not according to official data.

Research from the Health Protection Agency reveals that there are an estimated 1.7 million cases of foodborne illness in England and Wales each year – an average of 33,160 cases each week.

The foods most likely to cause food poisoning are poultry (29 per cent – this is the highest as proportionally more people eat chicken), red meat (17 per cent) and seafood (seven per cent). The foods least likely to cause food poisoning are cooked vegetables, fruit and rice.

Campylobacter is the most common cause of food poisoning in the UK. It was responsible for more than 371,000 estimated cases in England and Wales in 2009, resulting in more than 17,500 hospitalisations and 88 deaths. Campylobacter accounts for a third of the cost of the burden of foodborne illness in England and Wales, estimated at more than £583m in 2008.

Listeriosis, the foodborne illness caused by listeria, is relatively rare but listeria causes more deaths from food poisoning in the UK than other foodborne bugs. Vulnerable groups of the population are at increased risk.

So please keep things in perspective and remember to wash the food, your hands and the utensils before preparing and cooking food.

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Pope Francis, food and the mystics

pope francisAlmost every article I have read about the new Pope Francis mentions his humility, the simplicity of his home, his dedication to serving the poor and the fact that he cooks for himself.

This led me to wonder what he eats.

According to an article in the Argentinian newspaper La Nacion in 2009, he chooses healthy frugal food and occasionally drinks a glass of wine. He is said to like fruit, skinless chicken and salads. When in Buenos Aires, he apparently never ate out in restaurants. He would eat by himself and would not even join meals at parish churches in his diocese. On the rarest of occasions, he might break from his routine of eating in his own quarters to visit a nunnery to enjoy bagna cauda – a fondue of anchovies, garlic and olive oil.

The simplicity of Pope Francis’ diet reminds me of the story of Daniel and his friends in the Christian Bible (Daniel 1).

King Nebuchadnezzar of Babylonia attacked Jerusalem and surrounded the city. He captured King Jehoiakim and seized treasures from the Temple.

a Daniel_befrore_NebuchadnezzarNebuchadnezzar then ordered his chief official, Ashpenaz, to select some young men from the noble and royal families of the Israelite exiles to serve in his court. They had to be handsome, intelligent, well-trained, quick to learn, and free from physical defects. Ashpenaz was to teach them to read and write the Babylonian language. The king also gave orders that every day they were to be given the same food and wine as the members of the royal court. After three years of this training they were to appear before the king. Among those chosen were Daniel, Hananiah, Mishael, and Azariah, all of whom were from the tribe of Judah. The chief official gave them new names: Belteshazzar, Shadrach, Meshach, and Abednego.

Daniel made up his mind not to let himself become ritually unclean by eating the food and drinking the wine of the royal court, so he asked Ashpenaz to help him. Ashpenaz was sympathetic to Daniel but was afraid of the king. So he said to Daniel, “The king has decided what you are to eat and drink, and if you don’t look as fit as the other young men, he may kill me.”

So Daniel went to the guard whom Ashpenaz had placed in charge of him and his three friends. “Test us for ten days,” he said. “Give us vegetables to eat and water to drink. Then compare us with the young men who are eating the food of the royal court, and base your decision on how we look.”

He agreed to let them try it for ten days. When the time was up, they looked healthier and stronger than all those who had been eating the royal food. So from then on the guard let them continue to eat vegetables instead of what the king provided.

God gave the four young men knowledge and skill in literature and philosophy. In addition, he gave Daniel skill in interpreting visions and dreams.

At the end of the three years set by the king, Ashpenaz took all the young men to Nebuchadnezzar. The king talked with them all, and Daniel, Hananiah, Mishael, and Azariah impressed him more than any of the others. So they became members of the king’s court. No matter what question the king asked or what problem he raised, these four knew ten times more than any fortune teller or magician in his whole kingdom. Daniel remained at the royal court until Cyrus, the emperor of Persia, conquered Babylonia.

Daniel was not alone in his experience with food. Mystics of all traditions teach that diet influences spiritual awareness.

plant based diets

Many spiritual masters of the East, including Hindus, and various schools of yoga, divide foods into three basic categories: Sattvic (pure), Rajasic (kingly), and Tamasic (impure). They teach that this last category of foods, which includes all flesh foods and eggs, is to be completely avoided. A sattvic diet consists of fresh, simple foods including: grains, beans, vegetables, fruits, seeds, nuts, and dairy. Sattvic foods are said to promote mental clarity, relaxation, meditation, and spiritual experience including inner visions. A rajasic diet includes very rich, spicy food, and a tamasic diet includes meat and alcohol. These are said to stimulate passions, promote mental agitation, and have an adverse effect upon concentration in meditation.

Those who take up the practices concerning the lower centres in the body, do take meat … but those who are anxious to rise above body consciousness and go into the Beyond have of necessity to eschew all that. This is the Path I have put before you. Liberation or salvation is something which starts only when you rise above body consciousness. For that reason, vegetarianism is the first essential.

(Kirpal Singh, The Night is a Jungle, published by Sant Bani Ashram of New Hampshire).

Guru Kabir, a great Master from Northern India, loved by Sufis, Sikhs, Jains, and Hindus alike, said:

The man who eats meat is a demon in human form. Keep away from him – his company will ruin your meditation.

(Kabir: the Weaver of God’s Name, Radha Soami Satsang Beas).

According to these teachers, the bad karma and other negative effects of flesh-eating apparently to some degree darkens one’s inner vision, interfering with the quality of one’s meditation, making it more difficult to reach the required deep levels of tranquility, clarity and concentration.

The concept of diet affecting spiritual awareness is not confined to Eastern mystics.

Many early Christians were vegetarian; also Clement of Alexandria, Origen, John Chrysostom, and Basil the Great. In some early church writings, Matthew, Peter and James (brother of Jesus and first leader of the Aramaic-speaking Jerusalem Church) were said to be vegetarian. According to the historian Eusebius, the Apostle “Matthew partook of seeds, nuts and vegetables, without flesh.” Many monasteries in ancient times practised vegetarianism and continue to do so.

clement of alexandriaClement of Alexandria wrote,

It is far better to be happy than to have your bodies act as graveyards for animals.

Modern day Seventh Day Adventists, for example, advocate a vegetarian diet.

Most conventional world religions in the West condone flesh-eating, but many esoteric traditions which have practised various forms of mysticism, are consistent in their agreement about the need for contemplative mystics to abstain from the flesh. The list of Western vegetarian paths includes: the Pythagoreans, followers of the Hermetic philosophy of Egypt, the Sethians, Theraputae, Essenes, the original Jewish Christians called Ebionites, the Gnostic religions, Manichaeans, some Catholic monasteries, some monasteries associated with the Orthodox Church – including the great mystery school on Mount Athos in Greece – and the Sufi mystics of Islam.

It may be no coincidence that the predominantly plant-based diet of Daniel and spiritual masters of many traditions, is virtually identical to that advocated by modern science. A diet which is believed to enhance spiritual openness also protects against cancer, heart-disease, stroke, diabetes, dementia, arthritis and the general ravages of aging.

Pope Francis’s simple diet may not only have helped to deepen his spiritual practice but also given him the physical strength to take on this monumental role at the age of 76. May he prove to be as wise, knowledgeable and visionary as Daniel.

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Which foods are best for your health?

Do you ever feel bewildered by all the conflicting and contradictory information on nutrition and health?

Should you buy couscous or rice?  Salmon or tuna?  Pineapple or prunes?

Would you like a simple guide to help you with your shopping?

Fortunately, scientists at Yale University have come to your rescue and developed a score for the “overall nutritional quality” of a food.

Very simply, this score reflects the ratio of beneficial nutrients to harmful nutrients in a food.  It also takes account of the strength of the association of these nutrients with health.  For example, trans fat has a strong association with heart disease, so the value for trans fat is weighted, which substantially lowers the overall score for foods containing it.

The score is called the Overall Nutritional Quality Index, or ONQI.  The higher the score, the healthier the food.

David Katz and colleagues at Yale say:

ONQI is a measure analogous to density – just as the density of diamond does not vary with the size of the stone, the nutritiousness of broccoli does not vary with portion size

So what do you think?  Please leave a comment below and tell me if you find this helpful or if you have any questions.

ONQI graphic

Overall Nutritional Quality Index


Katz, D. et al.  Performance characteristics of NuVal and the Overall Nutritional Quality Index (ONQI).  Am J Clin Nutr April 2010, vol. 91 no. 4 1102S-1108S

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