On celery, seduction, science and salad

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

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 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).

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.

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.

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.

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.

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
Minerals
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
Vitamins
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
Lipids
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).

Compound	Percentage
Limonene	72.16
beta-Selinene	12.17
n-butyl phthalide	2.56
Lingustilide	2.41
alpha-Selinene	2.05
Linalool	1.48
alpha-Pinene	1.05
Myrcene	0.95
Sabenene	0.76
r-Cymene	0.74
Epoxycaryophyllene	0.55
Eudesmol	0.29
Caryophyllene	0.17
Thymol	0.17
Isopulegone	0.16
Cinnamic aldehyde	0.15
Carvone	0.09
alpha-lonone	0.05
Geranyl acetate	0.04
beta-Phellandrene	0.02
Pentyl benzene	0.02
Camphene	Traces
beta-Pinene	Traces
3-carene	Traces
alpha-Phellandrene	Traces
(Cis) beta-Ocimene	Traces
(Trans)beta-Ocimene	Traces

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

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

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

Anti-cancer

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

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

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.

Aphrodisiac

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

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.

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).

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, parsley and lime juice – Jane Philpott at http://www.cookingforhealth.biz

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

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 – Jane Philpott at http://www.cookingforhealth.biz

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.

Why?

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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References

(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, http://www.ars.usda.gov/nutrientdata

(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  http://www.ars-grin.gov/duke/index.html

(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. http://lpi.oregonstate.edu/books.html

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(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.

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Alzheimer’s Disease, metabolic disorders and the role of diet

Accumulating evidence for the role of metabolic disorders such as insulin resistance, diabetes, obesity and hypertension in increasing the risk of Alzheimer’s disease and vascular dementia, is reviewed in a new paper published this month in the Archives of Neurology.

In the same journal, compelling evidence is presented that higher pre-diagnosis total cholesterol, low-density lipoprotein cholesterol, and diabetes are associated with faster cognitive decline in patients with incident Alzheimer’s disease.

A cohort of 156 patients with incident Alzheimer’s Disease (mean age 83 years) were followed for up to 10 years.  Changes in a composite score of cognitive ability were monitored from diagnosis onwards.

“These findings indicate that controlling vascular conditions may be one way to delay the course of Alzheimer’s, which would be a major development in the treatment of this devastating disease as currently there are few treatments available to slow its progression,”

said Yaakov Stern, Ph.D., a professor at the Taub Institute for the Research on Alzheimer’s Disease and the Aging Brain and director of the Cognitive Neuroscience Division of the Gertrude H. Sergievsky Center at Columbia University Medical Center, and senior author of the paper.

“Preventing heart disease, stroke and diabetes – or making sure these conditions are well managed in patients diagnosed with them – can potentially slow the disease progression of Alzheimer’s,” said Dr. Stern.

Diets high in fruit, vegetables, fibre and unsaturated fats, and low in sugar, salt and saturated fat are known to reduce the risk of a range of chronic conditions, such as diabetes, heart disease and stroke.  This means eating more plant-based foods and less processed and animal-based foods.

Stabilising blood sugar is crucial.  This may be done by eating a diet with a low glycaemic load, that is, one that includes moderate quantities of complex carbohydrates which release glucose slowly into the bloodstream.  Whole grains, such as whole-wheat bread, brown rice, quinoa, millet and buckwheat are valuable for helping to ensure smooth regulation of blood sugar.  In contrast, highly refined carbohydrates, such as white bread, white rice, white pasta and table sugar, create a roller-coaster of blood sugar highs and lows, which if left unchecked, can ultimately give rise to insulin resistance and eventually to diabetes.  Potatoes release sugar into the bloodstream almost as fast as table sugar and thus should be eaten sparingly, unless you are lean and exercise regularly.  Consuming protein with carbohydrates at every meal has also been found to help regulation of blood sugar.

Increasing the quantity of vegetables and fruit in the diet is also vital.  Blood sugar levels are easier to maintain if vegetables are emphasized more than fruit, as some fruit contains a lot of sugar.  A minimum of 5 portions of fruit and vegetables per day is recommended.  For easy tips for increasing the amount of fruit and vegetables in your diet please click here.

Unsaturated fats found in plant oils, such as olive oil and the oils of nuts and seeds, and in oily fish, are beneficial for preventing heart disease and other vascular health conditions.  For practical suggestions for ways to incorporate more healthy unsaturated fats in your diet please click here.

For information and practical tuition in how to put all these recommendations together to create fabulous food that protects you from diabetes, heart disease and Alzheimer’s Disease, please come to a Cooking for Health course, run by nutrition expert, Dr Jane Philpott.

Soybean product may be of benefit in preventing Alzheimer’s disease

Scientists in Taiwan have published a paper in the February 2009 edition of the Journal of Agricultural and Food Chemistry indicating that an enzyme, nattokinase, which is found in a fermented soybean product called natto, has powerful ability in lab experiments to prevent formation of the clumps of tangled protein (amyloid fibrils) observed in Alzheimer’s disease.

More than 20 unrelated proteins can form amyloid fibrils in the body, which are related to various diseases, such as Alzheimer’s disease, prion disease, and systematic amyloidosis.  Enhancing amyloid clearance is one of the targets of the therapy of these amyloid-related diseases. Although there is debate on whether the toxicity is due to amyloids or their precursors, research on the degradation of amyloids may shed light on the prevention or alleviation of these diseases.

In this Taiwanese study, nattokinase degraded several kinds of amyloid fibrils suggesting its possible use in the treatment of amyloid-related diseases.

Natto is a traditional Japanese food made from fermented soybeans and is a popular breakfast dish.  For some, natto is an acquired taste due to its powerful smell, strong flavour and sticky consistency.

Natto is made from soybeans, typically a special type called natto soybeans.  Smaller beans are preferred as the fermentation can progress to the centre of the bean more easily.  The beans are washed and soaked in water for 12 to 20 hours, which causes the beans to swell.  Next, the soybeans are steamed for 6 hours, although a pressure cooker can be used to reduce the time.  The beans are then mixed with the bacterium Bacillus subtilis natto, known as natto-kin in Japanese.  From this point on, care has to be taken to keep the ingredients away from impurities and other bacteria.  The mixture is fermented at 40°C for up to 24 hours.  Afterwards the natto is cooled, then aged in a refrigerator for up to one week to add stringiness.  During the ageing process at a temperature of about 0°C, the bacteria develop spores, and enzymes break down the soybean protein into its constituent amino acids.  For this reason, the high protein content of the soybean is in a very digestible form. 

In addition to its high protein content, natto is rich in fibre, vitamin C, vitamin K, calcium, iron, potassium, phosphorus and magnesium.  In common with other soybean products, natto contains significant quantities of the isoflavone phytonutrients including genistein and daidzein, which are believed to have cancer-protective properties.

Natto is believed to have numerous health benefits and there is some medical research to support this.  The enzyme nattokinase is a serine protease which may reduce blood clotting by direct fibrinolysis of clots and inhibition of the plasma protein plasminogen activator inhibitor 1[i].  Clinical trials are needed to confirm laboratory studies.  An extract from natto containing nattokinase is available as a dietary supplement.

Vitamin K, which is present in significant amounts in natto, is involved in the formation of calcium-binding groups in proteins, assisting the formation of bones and preventing osteoporosis.  Vitamin K1 is found naturally in seaweed, liver and some vegetables, while vitamin K2 is found in fermented food products such as cheese and miso.  Natto has very large amounts of vitamin K2, approximately 870 mg per 100 g natto.

Natto is reported to contain substantial levels of a natural product called pyrroloquinoline quinone, which has been shown to stimulate DNA synthesis in cultured human fibroblasts, modulate immune response, and reduce liver injury, cataract formation and lipid peroxidation[ii].   

 A study reported in 1996 suggested that natto may have benefits in reducing cholesterol levels in people whose cholesterol and triglyceride levels are high[iii].

In January 1997, a Japanese television programme called Revealed! Encyclopaedia of Living recommended two portions of natto per day as a means of losing weight in only two weeks.  With the Japanese struggling with overweight and obesity this hit a nerve, and by lunchtime the next day national stocks of natto had sold out.    Whilst it is the case that natto has a relatively low number of calories per g of protein and a high nutrient density, it will only contribute to weight loss if consumed as part of a healthy diet, high in whole grains, vegetables, fruits and unsaturated fats, and low in saturated fats, salt and sugar, combined with plenty of exercise.

The most popular way to eat natto is to put it in a small bowl, add a little soy sauce and some finely-chopped spring onion and/or some mustard, mix the ingredients together and serve on some steamed rice.  Natto can also be added to miso soup to create a rich and nourishing dish, which smells a little like capuccino.

Natto can be purchased in the UK from specialist suppliers of Japanese food, such as the Japan Centre  and Japanese Kitchen.

Learn how to cook with natto and other soybean products such tempeh and tofu at popular Cooking for Health classes  held throughout the year in Somerset, UK .

Jane Philpott

 

References

[i]  Fujita M et al (December 1993). “Purification and characterization of a strong fibrinolytic enzyme (nattokinase) in the vegetable cheese natto, a popular soybean fermented food in Japan”. Biochemical and Biophysical Research Communications 197 (3): 1340–1347.

[ii] Kumazawa, T.  et al. Levels of pyrroloquinoline quinone in various foods.  Biochem J. (1995) 307: 331-333

[iii] National Cardiovascular Center, Osake, Japan (April 2006). “Examining the effects of natto consumption on lifestyle-related disease prevention“

Mediterranean diet may help prevent prostate cancer

Recently reviewed evidence relating diet and prostate cancer suggests that a traditional Cretan Mediterranean style diet based on a variety of plant foods (fruits, vegetables, wholegrain cereals, nuts and legumes), olive oil as the main source of fat, moderate to low intake of dairy foods, moderate to high intake of fish and moderate intake of wine, mostly with meals, may be helpful in reducing prostate cancer risk.

A recent meta-analysis of prospective cohort studies using a score to assess adherence to a Mediterranean diet found that stronger adherence was associated with reduced all cause, cardiovascular and cancer mortality, as well as decreased incidence of Parkinson’s and Alzheimer’s diseases [i].

Two intervention studies have supported the benefits of a Mediterranean style diet on metabolic risk factors [ii] [iii].  In a Spanish study, men and women with elevated levels of cardiovascular risk factors were randomised to either of two ‘Mediterranean’ diets and provided with either olive oil and nuts, or to a control low fat diet.  After 3 months the Mediterranean diet groups had lower mean plasma glucose, systolic blood pressure and total/HDL cholesterol ratio than the control group [ii].  Italian adults with the Metabolic Syndrome were randomised to a ‘Mediterranean’ diet or a ‘prudent’ diet, both with similar macronutrient (carbohydrate, protein, fat) composition.  The ‘Mediterranean’ diet was associated with greater improvements in markers of vascular risk and endothelial function than the control group [iii].  In both studies the ‘Mediterranean’ diet groups received more nutrition education than the control groups.

The Lyon Heart Study demonstrated that a modified Cretan diet low in butter and meats, and high in fish, fruits and enriched with alpha-linolenic acid from canola oil was more effective than a ‘prudent’ diet in the secondary prevention of coronary events and overall mortality [iv]. 

Simopoulos [v] notes that the traditional Greek diet resembles the Paleolithic diet in terms of fibre, antioxidants, saturated and monounsaturated fat, thus is consistent with human evolution.  While traditional diets must reflect regionally available foods, the dietary principles of the traditional Greek diet may be applied in many countries.  The evidence suggests that a traditional Greek or Cretan style diet is consistent with what humans have evolved to consume and may protect against common chronic diseases, including prostate cancer.

For information and practical tuition in how to incorporate the dietary principles of the Mediterranean diet into your own cooking, why not come along to a Cooking for Health course, run throughout the year in Somerset, UK.

Jane Philpott

References

[i] Sofi, F., Cesari, F., Abbate, R., Gensini, G F., Casini, A. Adherence to Mediterranean diet and health status: meta-analysis.  BMJ 2008: 337: a1344.

[ii] Estruch, R., Martinez-Gonzalez, M A., Corella, D. et al.  Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomised trial.  Ann Intern. Med. 2006: 145: 1-11.

[iii] Esposito, K., Marfella, R., Ciotola, M. et al.  Effect of a Mediterranean-style diet on endothelial dysfunction and markers of vascular inflammation in the metabolic syndrome: a randomised trial.  J Am Med Assoc 2004; 292: 1440-6.

[iv] de Lorgeril, M., Salen, P. Modified Cretan Mediterranean diet in the prevention of coronary heart disease and cancer.  In Simopoulos A,P., Visioli, F. eds.  Mediterranean Diets.  World Review Nutr. Diet. Basel: Karger, 2000: 1-23.

[v] Simopoulos, A P. The traditional diet of Greece and cancer.  Eur J Cancer Prev 2004; 13:219-30.

Mediterranean diet may prevent dementia

Eating a Mediterranean diet appears to be associated with less risk of mild cognitive impairment – a stage between normal ageing and dementia – and of transitioning from mild cognitive impairment into Alzheimer’s disease, according to a report in the February issue of Archives of Neurology.

“Among behavioural traits, diet may play an important role in the cause and prevention of Alzheimer’s disease”, the authors write as background information in the article.  Previous studies have shown a lower risk for Alzheimer’s disease among those who eat a Mediterranean diet, characterised by high intakes of fish, vegetables, legumes, fruits, cereals and unsaturated fats, low intakes of dairy products, meat and saturated fats and moderate alcohol consumption.

Nikolaos Scarmeas, M.D., and colleagues at Columbia University Medical Center, New York, calculated a score for adherence to the Mediterranean diet among 1,393 individuals with no cognitive problems and 482 patients with mild cognitive impairment.  Participants were originally examined, interviewed, screened for cognitive impairments and asked to complete a food frequency questionnaire between 1992 and 1999.

Over an average of 4.5 years of follow-up, 275 of the 1,393 who did not have mild cognitive impairment developed the condition.  Compared with the one-third who had the lowest scores for Mediterranean diet adherence, the one-third who had the highest scores for adherence to the Mediterranean diet had a 28 percent lower risk of developing mild cognitive impairment, and the one-third in the middle group for Mediterranean diet adherence had a 17 percent lower risk.

Among the 482 with mild cognitive impairment at the beginning of the study, 106 developed Alzheimer’s disease over an average of 4.3 years of folllow-up.  Adhering to the Mediterranean diet also was associated with a lower risk for this transition.  The one-third of participants with the highest scores for Mediterranean diet adherence had 48 percent less risk and those in the middle one-third of Mediterranean diet adherence had 45 percent less risk than the one-third with the lowest scores.

The Mediterranean diet may improve cholesterol levels, blood sugar levels and blood vessel health overall, or reduce inflammation, all of which have been associated with mild cognitive impairment.  Individual food components of the diet also may have an influence on cognitive risk.  “For example, potentially beneficial effects for mild cognitive impairment or mild cognitive impairment conversion to Alzheimer’s disease have been reported for alcohol, fish, polyunsaturated fatty acids (also for age-related cognitive decline) and lower levels of saturated fatty acids,” they write.

The study’s authors conclude that additional research is needed to confirm the role of this or other dietary factors in the development of cognitive impairment and Alzheimer’s disease.

Learn more about how to cook healthy food and prevent the development of chronic diseases at Cooking for Health classes held in Somerset, UK with Jane Philpott, MA (Oxon), MSc, PhD.

Dementia – can it be prevented with an optimum diet?

There is evidence from epidemiological studies that dietary and lifestyle factors may reduce the risk of dementia [i].  Studies of centenarians in the Japanese prefecture of Okinawa, for example, have indicated that they have dementia rates 30 to 40 per cent lower than similarly aged Americans. 

Research at Oxford University and elsewhere has provided clear evidence that Alzheimers is not an inevitable part of ageing but is a disease [ii].  There is also evidence of a correlation between coronary heart disease, homocysteine level and risk of dementia [iii, iv].
 
It is well-established from numerous long-term health studies that energy-dense diets high in saturated fat, sugar and salt, and low in fruit, vegetables, fibre and essential fatty acids increase the risk of developing heart disease (World Health Report 2002).  There is therefore significant interest in whether such diets may also increase the risk of developing dementia and whether homocysteine level is a modifiable risk factor.

The potential role of folate and vitamin B12 in reducing homocysteine levels has been investigated by the University of Oxford Project to Investigate Memory and Ageing – OPTIMA – by the US National Institute on Aging and by the Alzheimer’s Disease Co-operative Study.  Recent results suggest that high doses of B vitamins do not slow cognitive decline in people with Alzheimer’s disease (see Reuters news report, October 2008).  The study did not look at whether lowering homocysteine much earlier in life would prevent or delay Alzheimer’s.

The problem with this type of clinical trial is that the effects of a small number of nutrients are examined in isolation, often at much higher doses than would be typical in a normal diet.  In real life, the protective effects of a diet are likely to occur due to complex interactions between a large number of nutrients present in relatively small amounts.