Whether diet, vitamins, or supplements can benefit patients with vitiligo remains unclear

WASHINGTON – Many patients with vitiligo are interested in treating their condition with vitamins, supplements, or a modified diet, but research on whether these measures have an impact remains limited, Nada Elbuluk, MD, said at the annual meeting of the American Academy of Dermatology.

Dr. Nada Elbuluk

While the literature suggests that supplements with antioxidant properties benefit patients who are receiving phototherapy for vitiligo, “we need more well designed, controlled studies in the future to know where this belongs in our treatment armamentarium,” said Dr. Elbuluk of the department of dermatology at the University of Southern California, Los Angeles.

During a session at the AAD meeting, Dr. Elbuluk, who is also director of the pigmentary disorders clinic at USC, reviewed the evidence for the use of these adjunctive therapies in patients with vitiligo.

Vitamins

The pathogenesis of vitiligo includes the overproduction of reactive oxygen species and oxidative stress, factors that contribute to melanocyte damage and death. In addition, many patients with vitiligo are deficient in certain vitamins and minerals, the basis of the hypothesis that supplementation could be beneficial, according to Dr. Elbuluk.

Vitamin B₁₂ and folic acid contribute to DNA repair, synthesis, and methylation, and researchers have hypothesized that these vitamins also play a role in melanin synthesis. In a review of the literature, Dr. Elbuluk and her colleagues found four studies that evaluated vitamin B₁₂ and folic acid in vitiligo. In one study, a controlled trial in which patients took B₁₂ and folic acid with and without phototherapy, the investigators observed no significant difference in repigmentation between groups. The other three studies were uncontrolled and thus provide an insufficient understanding of the effect of B₁₂ and folic acid, said Dr. Elbuluk.

Vitamin D is involved in melanocyte and keratinocyte growth and differentiation, and inhibits T cell activation. Data indicate that low vitamin D levels are common in patients with vitiligo and comorbid autoimmune diseases. In one study, patients who received narrow-band UVB had an increase in vitamin D levels that could contribute to photo-induced melanogenesis, and an open-label study indicated that patients who took vitamin D daily (without phototherapy) for 6 months had an increase of repigmentation over time. “Topical vitamin D analogs have also been used in vitiligo treatment with varying success,” Dr. Elbuluk noted.

“I check vitamin D levels on my patients and make sure that they are within normal range. But I think the degree of supplementation and its role in vitiligo needs to be further elucidated,” she said. And because vitamin D is fat soluble, there is a risk of toxicity if a patient takes too much.

Vitamin C, vitamin E, and alpha-lipoic acid have antioxidant properties. In a double-blind, randomized, controlled trial, one group of patients took vitamins C and E and alpha-lipoic acid for 2 months before and during treatment with narrow-band UVB twice per week (Clin Exp Dermatol. 2007 Nov;32[6]:631-6). Another group underwent phototherapy without supplementation. A significantly greater proportion of patients who received the antioxidants obtained more than 75% repigmentation compared with those who did not. In another study, 73% of patients who received oral vitamin E and narrow band UVB phototherapy had marked to excellent repigmentation, compared with 55.6% of those who had phototherapy only (J Clin Pharmacol. 2009 Jul;49[7]:852-5).

The results of these studies support the idea that antioxidants can stabilize disease, reduce oxidative stress, and improve the effect of phototherapy, Dr. Elbuluk said.