One of the most frequent questions asked by my patients and their families is about the role of diet and supplements in the treatment of their vitiligo. The image to the left shows the supplements one of my patients was taking every day, many of them twice per day. A quick search on the internet will return many claims about how special diets, vitamins, and other supplements treat or even cure vitiligo, and others to avoid, as they supposedly make vitiligo worse. For example, there is a long-standing belief that drinking milk while eating fish can cause vitiligo. Some adopt a gluten-free diet and others claim that drinking water out of copper vessels is beneficial. Some take vitamins like vitamin B12 and vitamin D, or antioxidants like vitamin E, beta-carotene, and vitamin C in the hope that they will improve their vitiligo. I have heard parents say, “If there’s anything I can do for my child with vitiligo, then I’m willing to do it”, like changing what they prepare for meals or purchasing vitamin supplements.
Patients often feel that this is one thing they can control in their treatment strategy, and they want to try whatever they can. But many times they can hurt, rather than help, their disease. For example, I have seen posts on the internet that vitiligo patients are taking things to “boost their immune system” to help their vitiligo, however this is probably a bad idea, since it’s an overactive immune response (autoimmunity) that causes vitiligo in the first place (read more about that here). In fact, all of the effective treatments for vitiligo actually suppress the overactive immune system. This is an example of how making assumptions and guesses about the best treatments for vitiligo could be harmful instead of helpful. In this post I discuss some of the misconceptions about diet and supplements in vitiligo, as well as what evidence is out there for using them.
Some of these supplements and dietary recommendations are born from a hint of truth, but many come from a misinterpretation. For example, it is true that vitiligo patients may be deficient in a number of vitamins. Vitamin D is probably the most common, because many of us are deficient in this vitamin, and vitiligo patients may be more so because of their need to avoid the sun to prevent burning of their sensitive white spots. But this doesn’t mean that their low vitamin D caused, or is even affecting, their vitiligo, and supplementing their vitamin D may be a good idea for their overall health, but is unlikely to help their vitiligo. Some have heard that vitiligo is partly due to increased reactive oxygen species in melanocytes, you can read more about that here. So some believe that taking antioxidants should help the disease, and many dermatologists recommend this for their patients. However it is important to remember that no matter how much things seem to make sense, we can’t know for sure if this approach will help vitiligo until they’re tested in clinical trials.
Another example is supplementing vitamin B12 – this vitamin is more commonly deficient in vitiligo patients compared to the general population. The reason for this is a little complicated, but it’s important to understand, so I will explain. Vitamin B12 deficiency is usually a result of pernicious anemia, an autoimmune disease in which gastric parietal cells are destroyed in the stomach. These cells are important because they make a protein called intrinsic factor, which is necessary to help absorption of vitamin B12 from the stomach into the blood. Without intrinsic factor, vitamin B12 cannot be absorbed through the diet, and patients get low blood count, or anemia, because red blood cells require vitamin B12 for normal development. The treatment for this is regular injections of vitamin B12 in order to bypass stomach absorption. So what does any of this have to do with vitiligo? Vitiligo patients can also develop pernicious anemia, and this is more common than in people without vitiligo. We think that some of the genes that contribute to vitiligo and pernicious anemia are the same, which is why patients, and their family members, are a little more likely to get pernicious anemia as well. So, vitiligo patients may indeed have low vitamin B12 if they also have pernicious anemia, but this is very uncommon. And if they do, in fact, have pernicious anemia and low B12, then taking oral supplementation is unlikely to help, because it cannot be efficiently absorbed. So supplementation of vitamin B12 for vitiligo patients is sometimes necessary, but only in those who also have pernicious anemia, and then it must be injected. So there is no evidence that vitiligo patients should take extra vitamin B12, or that it will help their vitiligo.
The rationale for eating a gluten-free diet is similar to the pernicious anemia/vitamin B12 story. Some people have an adverse reaction to eating gluten in their diet, a condition called celiac disease. In these patients gluten initiates inflammation in the intestines, which usually causes stomach pain, bloating, and diarrhea. Long-term, untreated disease increases the risk of developing an intestinal lymphoma, and so it is important for those patients to follow a gluten-free diet (and this is not easy), to clear their symptoms and decrease the risk of lymphoma. But fortunately, most people do not have this condition, and following a gluten-free diet is unnecessary. Like pernicious anemia, vitiligo patients have a slightly increased risk of also having celiac disease, and so if they’re having intestinal symptoms they should have tests for diagnosis. If they have the disease, then a gluten-free diet will help their intestinal symptoms, but is unlikely to help their vitiligo.
I usually explain it to patients this way: your genetic makeup is partially responsible for getting a number of autoimmune diseases, including pernicious anemia and celiac disease. So they may cause multiple diseases in a small number of patients. But treating one disease is not likely to help the other. Imagine a snow-capped mountain after an earthquake, on which two avalanches begin, one on each side. The cause of both avalanches is the same, but once they’re initiated, they’re independent and each will follow its own course, and stopping one won’t affect the other. Many vitiligo patients also have thyroid autoimmunity (about 20%) and must take levothyroxine (Synthroid) to alleviate the symptoms. But so far it doesn’t appear that treating their thyroid disease helps their vitiligo.
So there is a lot of misinterpreted data out there, some with a partial truth, but none that clearly implicates dietary changes or vitamin supplementation as helpful for treating vitiligo. There are plenty of individuals who claim that they’ve had responses to supplements, but in order to know for sure, a clinical trial would have to be conducted, in which one group of patients changes the diet or takes a supplement and another group doesn’t (takes placebo) and then their vitiligo is compared. A trial like this is not easy, because a large number of patients would have to be enrolled and followed for a long time (a year or more) in order to see a difference. This would be very expensive, and funding is difficult to find for a trial like this, since diets and supplements cannot be patented, and there is no money to be made on a positive result. One trial was conducted to test this, but the supplements were combined with a standard treatment for vitiligo, narrow-band UVB (nbUVB), as it would be easier to see a positive response in a smaller number of patients in a shorter time. Thus the trial tested the ability of these supplements to improve the response to nbUVB. The trial did report a better response in those who took the supplements and received nbUVB than those who took placebo with nbUVB, but the authors agreed that additional studies would have to be conducted to know if they are really useful.
One thing is pretty clear – there are a number of good treatments for vitiligo that have been tested through clinical trials that reported significant results, while the effect of supplements is not yet clear. Therefore, patients who want to treat their vitiligo should first pursue the treatments that we know work (listed here), and then discuss supplementation with their doctor. While supplements may or may not hurt the vitiligo (without trials and data we can’t know for sure), they can be expensive, which can be a hardship for patients, particularly if they turn out not to be effective. One more thing to keep in mind – supplements are not regulated by the Food and Drug Administration (FDA) in the US, or in any other country to my knowledge, and a recent study found that a large number of herbal supplements tested in the US didn’t contain any trace of the herb on the label. So many are spending money on supplements that are not what they claim. In the end, I tell my patients that most supplements are probably not harmful, and if they can afford them then they can try them. But I also tell them that if they’re just guessing about what supplement to take or dietary change to make (and most of these are just guesses), then they’re just as likely to harm their vitiligo as help it (while most things probably won’t do anything).
So what’s the answer? I guess it’s that it’s complicated, and that we don’t have enough information yet. But most supplements are unnecessary, time-consuming, and expensive. A few may someday be revealed to help a little bit, but probably won’t do a lot, or we would probably already know about them. I would recommend having a discussion with your doctor, and developing an informed plan for your treatment.