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There is a desperate longing in the majority of people with vitiligo for a cure, or for some way of alleviating the symptoms. This leads them to grasp at anything that might carry some hope. At times when the vitiligo is actively spreading people feel particularly helpless. Anything that would bring back a feeling of control may be tried.
Food, of course, is one area where it feels possible to bring some control to our lives. Manipulating the diet is sometimes helpful in treating some conditions like eczema. However, dramatic changes in the diet can cause other problems if not done with some knowledge or advice. For instance, in some cultures it has been suggested (without evidence) that avoiding white foods can lead to an improvement in vitiligo. This involves avoiding dairy foods which are a good source of calcium, particularly important for young children who need it to develop strong bones and teeth.
The body is a complex mechanism, made up of millions of cells and regulated by complex hormones and enzyme systems. A wide range of nutrients are needed to maintain this in a healthy functioning state. Not only are nutrients needed, but they themselves interact, inhibit, compete or rely on one another for effective functioning. This is why picking out one vitamin or mineral alone either as a cause of a problem or to take as a supplement is not usually helpful.
There are several vitamins and minerals involved in the production of melanin and enzymes involved in the process of pigmentation. Interest has focused especially on these as possibly having some effect on the course of vitiligo. If it was as simple as finding one malfunctioning nutrient, we would have had a cure long ago. Because vitiligo can improve spontaneously, it has sometimes been assumed that when this is happening it is due to something else e.g. treatment for another condition or a change of diet. This has led to reports, without a sound scientific basis, that certain nutrients can cure vitiligo. It has also led to more research into trying to understand how certain nutrients are involved in skin pigmentation. Such studies so far have been difficult to conduct, usually have small numbers of participants, and are mostly not very reliable. They can, however, help to build up our overall understanding of the connection between diet and vitiligo
Vitamin B12 and folic Acid
In patients with pernicious anaemia, vitamin B12 is not available to the body because the substance in the stomach needed for its absorption is not present. Pernicious anaemia is one of the auto-immune diseases associated with vitiligo. There have been occasional reports, in cases where both diseases exist in the same patient, that when the pernicious anaemia is treated by injections of vitamin B12 the vitiligo also improves. Montes noted in his studies of his patients with vitiligo that 10.7% had low levels of vitamin B12 in their blood. This work was done in Argentina where the diet is very different from UK. (Montes LF,Vitiligo, Nutritional Therapy; Westhoven Press .
Montes LF Vitiligo: Current Knowledge and Nutritional Therapy (2nd ed) Westhoven Press, Buenos Aires 2006
Folic acid contains substances which play a role in the pigmentation process. Vitamin B12 and folic acid work closely together. Both are needed to facilitate some biological processes and have been investigated, together, in research projects. One small study (15 participants in all) giving these two nutrients with vitamin C showed some re-pigmentation in half the patients (Montes et al. Cutis 1992; 50:39 - 42). A more recent randomised trial, (Tjioe et al. Acta Derm Venereol 2002; 82:369-372)of 28 patients treated with narrow band UVB for a year showed no added benefit of adding supplementary vitamin B12 and folic acid to the treatment. Another study (Julin L, Olsson MJ. Acta DermVenereol 1997;77;50:39-42) using these two vitamins with solar UV exposure showed an improvement, but the UV exposure was not standardised and there was no control group.
Para amino benzoic acid (PABA)
This is one of the components of folic acid which probably accounts for its apparent effect on vitiligo. It is an ingredient of some sunscreens as it can block some UV light. Although it has been reported to promote repigmentation, this is only in combination with other B complex vitamins. It has been reported to cause vitiligo in one case. (J Am. Academ Dermatol. 1983; 9:770}
Phenylalanine
Phenylalanine is an essential amino acid which is found in a normal diet. It may increase the body's tolerance to UVA. There are a few reports of some improvements in patients having UVA treatment when phenylalanine is added. This has improved outcomes and it is suggested that this warrants more investigation. ( Szczurko O. and Boon HS. A Systematic Review of Natural Health product treatment for vitiligo. BMC Dermatology 2008 8:2 – online publication)
Beta carotene
This is a precursor of vitamin A. In large doses it is deposited in the skin giving it a yellow tint. Some people have used this to colour the very white patches of vitiligo. It does not remain in the skin, so would need to be taken continuously to maintain the colour. In normal amounts in food it has a protective effect against damage by free radicals. Free radicals are toxic waste products produced as a result of a biochemical process in the body. They cause damage to tissue cells and are believed to be implicated in many chronic diseases.
Vitamin D
Vitamin D is only found in a few foods such as oily fish, cod liver oil, liver, milk, eggs and foods such as margarine, some milk powders and yogurts and some cereals are fortified with it in the UK. It is vital for bone health and can help to maintain a healthy immune system. About 90% of the requirement of vitamin D is synthesised by the body from the effect of UVB rays on the skin. There has been concern that in people with vitiligo continuous use of sunblock may prevent the body producing the vitamin itself. Most of the vitamin D is formed during the summer and only a small amount of exposure (15 – 20 minutes a day two or three times a week) will provide sufficient as well as body stores for the winter months when sunlight levels are lower. It is best to spread the exposure over the week. There is some debate about how much sun vitiligo patients should have as some is thought to be beneficial (Ref Dispatches No 32 page 8 July 2003)
Minerals
Copper, iron, zinc and calcium all have a role in the pigmentation process. Low levels of zinc and copper have been linked with premature greying hair. Low levels of both minerals have also been found in de-pigmented skin. Iron is also low in de-pigmented skin and has a role in the activation of tyrosinase. Tyrosinase is a copper requiring enzyme and is essential in the pigmentation process.
Antioxidants
Recent research has shown the importance of preventing tissue damage by free radicals. It is thought that a good supply of antioxidant nutrients can improve the immune system function and help prevent chronic diseases, such as heart disease and some cancers. Antioxidants neutralise these free radicals and protect against the damage. This is increasingly seen as an important factor in vitiligo too. The main antioxidant nutrients are vitamins A. C. E. carotene and folic acid, polyphenolic flavanoids and some minerals such as selenium, copper and zinc. Though selenium levels in the British diet have fallen in recent years a study showed that blood levels in vitiligo patients were not low. A recent randomised controlled trial (Dell’Anna et al. Clinical and Experimental Dearmatology, 32,631-636) showed that giving antioxidants with narrowband UVB improved the effectiveness of the light treatment.
Curcumin, (Turmeric)
In the diet has been shown to be reduce the effectiveness of treatment of vitiligo with pseudocatalase in a small study of asian patients who have a significant amount of turmeric in their diet.(Schallreuter K. Rokos.H. Indian J. Dermatol, Venreol, Leprol 72: 57-59)
Summary
It is clear that there is no simple nutritional answer to vitiligo. However, as a good supply of nutrients is required both to promote a healthy skin and in the pigmentation process, a good, varied diet is important.
The best way to ensure adequate amounts of these nutrients is by having as much variety as possible in the diet including plenty of fruit and vegetables (at least five servings per day). A variety of starchy foods as a basis for each meal and smaller servings of fat rich and highly processed foods is recommended. It is better to try and increase the nutrient rich foods in the diet than rely on too many supplements. Although supplements can have a place sometimes, there may still be unknown beneficial factors available in foods that are not provided by nutrients in tablet form.
Daphne Horder 2008 |
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