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 (theedibleflowershop.co.uk)

Chive and viola flower salad (theedibleflowershop.co.uk)

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).

Flower

Protein

 

Carb

 

Fat

 

Vit A

 

Folate

 

Vit C

 

Ca

 

Fe

 

Mg

 

K

 

 

g/100g

IU

μg/100g

mg/100g

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.

dandelions

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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Recipe

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

Ingredients

  • 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

Method

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

References

  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.http://ndb.nal.usda.gov/ndb/search/list
  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).

chloroxygen

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.

Aflatoxin

Aflatoxin

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.

Conclusion

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.

1-IMG_1896

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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References

1. Chloroxygen. http://www.herbsetc.com. [Online] http://www.herbsetc.com/Topics/PDF/chloro_bro_07.pdf.
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] http://www.quackwatch.org/01QuackeryRelatedTopics/DSH/chlorophyll.html.
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 http://www.fda.gov. [Online] 11 May 1990. http://www.fda.gov/downloads/Drugs/DevelopmentApprovalProcess/DevelopmentResources/Over-the-CounterOTCDrugs/StatusofOTCRulemakings/ucm110925.pdf.
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] http://www.nhs.uk/conditions/Lyme-disease/Pages/Introduction.aspx.
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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References

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.

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

Reference

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

If you have enjoyed this post and would like to know more about how to cook and eat to maintain or restore your health, please visit my website.  You can also stay in touch by signing up for my newsletter and by joining me on Facebook and Twitter.

Plant-based diet for treating heart disease

Coronary artery before and after plant-based diet (C. Esselstyn 2001)

Coronary artery before (left) and after (right) plant-based diet (Esselstyn CB Jr: Preventive Cardiology 2001;4: 171-177)

Few people realise that a plant-based diet not only prevents heart disease but can also reverse it. Choosing whole grains, fruits and vegetables and avoiding simple sugars, and saturated and trans fats, as in meat and dairy products, has been shown to result in regression of coronary atherosclerosis after 1 and 5 years in some studies (1) (2) and to continue for over 12 years in other studies (3).

In contrast, standard medical interventions for cardiac patients, such as coronary artery bypass, bypass grafts, atherectomy, angioplasty or stenting, treat only the symptoms, not the disease.  It is therefore not surprising that patients who receive these interventions alone often experience progressive disease, graft shutdown, restenosis, more procedures, progressive disability, and ultimately death from disease (4).

Caldwell Esselstyn MD persuaded 18 cardiac patients to continue with a plant-based diet for over 12 years. Adherent patients experienced no extension of clinical disease, no coronary events, and no interventions. This finding is all the more compelling when we consider that the original compliant 18 participants experienced 49 coronary events in the 8 years before the study (4).

Some patients believe that there is no need to change their diet if they have had heart surgery, stents inserted and/or are taking drugs like statins and aspirin.

A recently published international study (5) indicated that individuals (more than 31,000 men and women of an average age of 66 in this study) who chose whole grains, fruits, vegetables, nuts, and fish over meat, eggs and refined carbohydrates had a 35% reduction in cardiac death rates over 5 years. That’s a 35% reduction in addition to the decrease from surgery and optimal medical management. And these men and women were older, where you’d expect diet to be able to reverse less.

So it is never too late to make simple changes to your diet and lifestyle to improve your long-term health, whether you have medically-managed heart disease or not.

If you have heart disease, you can eat a wonderful variety of delicious, nutrient-dense foods:

  • All vegetables except avocado. Leafy green vegetables, root vegetables, vegetables that are red, green, purple, orange, and yellow – every colour of the rainbow
  • All legumes—beans, peas, and lentils of all varieties.
  • All whole grains and products, bread and pasta, that are made from them—as long as they do not contain added fats.
  • All fruits

You need to avoid:

  • Red meat, poultry and fish
  • Dairy products
  • Oils of all kinds (even olive oil)

 

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References

(1) Ornish, D. et al (1998). Intensive lifestyle changes for reversal of coronary heart disease. JAMA, Vol 280, No. 23, 2001-2007

(2) Ornish, D. et al (1990). Can lifestyle changes reverse coronary heart disease?  The Lancet, 21 July 1990, Vol 336, No. 8708, 129-133

(3) Esselstyn, C. (2001).  Resolving the coronary artery disease epidemic through plant-based nutrition.  Preventive Cardiology, 4, 171-177

(4) Esselstyn, C.  Updating a 12-Year Experience With Arrest and Reversal Therapy for Coronary Heart Disease (An Overdue Requiem for Palliative Cardiology).  Article on Caldwell Esselstyn’s website.

(5) Dehghan, M. et al. Relationship Between Healthy Diet and Risk of Cardiovascular Disease Among Patients on Drug Therapies for Secondary Prevention: A Prospective Cohort Study of 31 546 High-Risk Individuals From 40 Countries. Circulation, 4 December 2012, 126: 2705-2712

Diet and your eye sight

Recently one of my clients was diagnosed with age-related macular degeneration and was advised by a health professional to take supplements of the carotenoids lutein and zeaxanthin to prevent progression of this condition. Given that these supplements are expensive, she wanted to know if her investment would pay off.

As discussed below, the bottom line is that, to date, there is little scientific evidence to support the use of antioxidant supplements either to prevent or delay the progression of age-related macular degeneration. Indeed, there is evidence that such supplements may be harmful.

In contrast, there is scientific evidence that consumption of a plant-based diet with a variety of whole grains, vegetables and fruit has many benefits with regard to preventing and treating diseases like macular degeneration, and does no harm.  Further research is required in this area.

The best way to protect the health of your eyes is to eat plenty of different coloured vegetables and fruit; for example, broccoli, cabbage, kale, collard greens, green peas, spinach, courgettes, red and yellow peppers, winter squash, kiwi fruit, blueberries, oranges and mango.

What is age-related macular degeneration?

Age-related macular degeneration is an eye condition affecting older people, and involves the loss of the person’s central field of vision. It occurs when the macular (or central) retina in the eye develops degenerative lesions. The retina is the light-detecting membrane at the back of the eye. The macula contains a particularly high density of light receptors, especially cones (the receptors that detect colour) and so the macula is particularly important for seeing fine detail and objects directly in front of us. It plays a vital role in helping people to read, write, drive and perform other detailed tasks. It also enables us to recognise faces and see colour.

According to the World Health Organisation (1), globally, age-related macular degeneration ranks third as a cause of blindness after cataract and glaucoma; it is the primary cause in industrialized countries. Several forms of age-related macular degeneration exist.

Carotenoid pigments in the eye – lutein, zeaxanthin and meso-zeaxanthin

Pigments known as carotenoids are found within the eye. There are over 600 known carotenoids in nature but in the human eye, just three of these pigments – lutein, zeaxanthin and meso-zeaxanthin – form a concentrated ‘yellow spot’ in the macula, known as the macular pigment. This pigment has two main functions: it acts as an antioxidant and it filters light.

As short wavelength (blue) light passes through the retina to the photoreceptors and pigmented epithelial cells, reactive oxygen species are generated. The conversion of the light energy into a nerve impulse by the photoreceptors generates free radicals – unstable molecules which damage a variety 
of tissues – resulting in many of the diseases and conditions associated with ageing. Antioxidants in the eye are able to quench these free radicals, thereby protecting the eye from oxidative damage. Lutein, zeaxanthin and particularly meso- zeaxanthin are very effective antioxidants.

The pigments lutein and zeaxanthin can be found naturally in a number of food sources (2). For example, lutein can be found in yellow peppers, mango, bilberries and green leafy vegetables such as kale, spinach, chard and broccoli. Zeaxanthin can be found in winter squash, orange sweet peppers, broccoli, corn, lettuce, spinach, tangerines, oranges and eggs.

Blue light, because of its relatively high photon energy, more readily damages the retina than yellow or red light, which is less energetic. The macular pigment acts as a filter, particularly to blue light, and therefore protects against this damaging effect.

Given that the development of age-related macular degeneration is likely to involve a complex interaction of cellular and vascular factors, which may be promoted by light damage, oxidative stress, and inflammation, it is biologically plausible that a number of dietary components may be protective.

Effect of diet on age-related macular degeneration

The results of several epidemiological studies and clinical trials in the peer-reviewed scientific literature suggest that diets high in antioxidant nutrients (vitamins C and E, carotenoids such as lutein and zeaxanthin, fruit and vegetables that contain these nutrients, and non-nutritive antioxidants) or zinc are associated with a decreased occurrence of early or late age-related macular degeneration (3) (4). A high dietary intake of fat was associated with a higher prevalence or incidence of early or late age-related macular degeneration in numerous studies (5), whereas higher intakes of fish or omega 3 fatty acids were associated with lower rates of age-related macular degeneration (5).

Despite nutritional advice being available, awareness of the link between diet and eye health is poor. A survey conducted by the Eyecare Trust (6) found that Britons are oblivious to the fact that unhealthy lifestyles and obesity can substantially increase the risk of macular degeneration and ultimately blindness.

Efficacy of nutrient supplements for age-related macular degeneration

Some clinicians argue that it is difficult to obtain adequate amounts of the protective nutrients required for the eyes from a ‘normal’ diet. They thus prescribe high doses of nutrient supplements. But are these nutritional supplements effective?

A recently published Cochrane Review (7) identified four large, high-quality randomised controlled trials which included 62,520 people. The trials were conducted in Australia, Finland and the USA and investigated the effects of vitamin E and beta-carotene supplementation. These trials provide evidence that taking vitamin E and beta-carotene supplements is unlikely to prevent the onset of age-related macular degeneration. There was no evidence for other antioxidant supplements and commonly marketed combinations.

Another Cochrane Review (8) investigated whether progression of age-related macular degeneration may be slowed down in people who take antioxidant supplements (carotenoids, vitamins C and E) or minerals (selenium and zinc). The authors identified 13 randomised controlled trials which included 6150 participants; five trials based in the USA, two in the UK, two trials in Austria, and one trial in each of a further four countries (Australia, China, Italy and Switzerland). The review of trials found that supplementation with antioxidants and zinc may be of modest benefit in people with age-related macular degeneration. This was seen mainly in one large trial that followed up participants for an average of six years. The other smaller trials with shorter follow-up do not provide evidence of any benefit. Large well-conducted trials in a range of populations and with different nutritional status are required.

Safety of antioxidant nutrient supplements

Although generally regarded as safe, there is evidence that antioxidant supplements may have harmful effects. A Cochrane Review in 2008 (9) demonstrated that antioxidant supplements seem to increase mortality in sufferers of cancer and cardiovascular disease. This review was updated in 2012 (10) and found no evidence to support antioxidant supplements for primary or secondary prevention. Beta-carotene and vitamin E seem to increase mortality, and so may higher doses of vitamin A. The authors concluded that current evidence does not support the use of antioxidant supplements in the general population or in patients with various diseases in a stable phase, including gastrointestinal, cardiovascular, neurological, ocular, dermatological, rheumatoid, renal, endocrinological, or unspecified diseases.

Conclusion

The bottom line from all of this work is that, to date, there is little evidence to support the use of antioxidant supplements either to prevent or delay the progression of macular degeneration. Indeed, there is evidence that such supplements may be harmful.

In contrast, consumption of a plant-based diet with a variety of whole grains, vegetables and fruit has many benefits with regard to preventing and treating disease, and none of the disadvantages associated with nutritional supplements.  Further research and analysis of the literature is required in this area.

Further information and help

If you are suffering from a specific health problem or would just like to improve your general health and well-being, you will benefit from a personal nutrition consultation. Simple changes to diet and lifestyle can lead to significant improvements in the way you feel.  For a delicious recipe full of the carotenoids lutein and zeaxanthin, please click here.

References

(1) http://www.who.int/blindness/causes/priority/en/index8.html

(2) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1722697/

(3) http://www.ncbi.nlm.nih.gov/pubmed/16380590?dopt=Abstract

(4) http://informahealthcare.com/doi/abs/10.3109/09286580903450353

(5) http://www.ncbi.nlm.nih.gov/pubmed/14662593?dopt=Abstract

(6) http://www.eyecaretrust.org.uk/view.php?item_id=563

(7) http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD000253.pub3/abstract

(8) http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD000254.pub3/abstract

(9) http://www.ncbi.nlm.nih.gov/pubmed/18425980

(10) http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD007176.pub2/abstract