Dietary supplements have a role in the integrative treatment of vitiligo, largely through antioxidant pathways and as an adjuvant to phototherapy, Ammar Ahmed, MD, associate professor of dermatology at Dell Medical School at the University of Texas, Austin, said at the annual Integrative Dermatology Symposium.
Data on the use of dietary supplements for vitiligo are scarce and of limited quality, but existing studies and current understanding of the pathogenesis of vitiligo have convinced Dr. Ahmed to recommend oral Ginkgo biloba, vitamin C, vitamin E, and alpha-lipoic acid – as well as vitamin D if levels are insufficient – for patients receiving phototherapy, and outside of phototherapy when patients express interest, he said.
Melanocyte stress and subsequent autoimmune destruction appear to be "key pathways at play in vitiligo," with melanocytes exhibiting increased susceptibility to physiologic stress, including a reduced capacity to manage exposure to reactive oxygen species. "It's more theory than proven science, but if oxidative damage is one of the key factors [affecting] melanocytes, can we ... reverse the damage to those melanocytes with antioxidants?" he said. "I don't know, but there's certainly some emerging evidence that we may."
There are no human data on the effectiveness of an antioxidant-rich diet for vitiligo, but given its theoretical basis of efficacy, it "seems reasonable to recommend," said Dr. Ahmed. "When my patients ask me, I tell them to eat a colorful diet – with a lot of colorful fruits and vegetables." In addition, he said, "we know that individuals with vitiligo, just as patients with psoriasis and other inflammatory disorders, appear to have a higher risk for insulin resistance and metabolic syndrome, even after accounting for confounders," making a healthy diet all the more important.
Two case reports have described improvement with a gluten-free diet, but "that's it," he said. "My take is, unless stronger evidence exists, let your patients enjoy their bread." No other specific diet has been shown to cause, exacerbate, or improve vitiligo, he noted.
Dr. Ahmed offered his views on the literature on this topic, highlighting studies that have caught his eye on antioxidants and other supplements in patients with vitiligo:
Vitamins C and E, and alpha-lipoic acid: In a randomized controlled trial of 35 patients with nonsegmental vitiligo conducted at the San Gallicano Dermatological Institute in Rome, those who received an antioxidant cocktail (alpha-lipoic acid, 100 mg; vitamin C, 100 mg; vitamin E, 40 mg; and polyunsaturated fatty acids) for 2 months before and during narrow-band ultraviolet-B (NB-UVB) therapy had significantly more repigmentation than that of patients who received NB-UVB alone. Forty-seven percent of those in the antioxidant group obtained greater than 75% repigmentation at 6 months vs. 18% in the control arm.
"This is a pretty high-quality trial. They even did in-vitro analysis showing that the antioxidant group had decreased measures of oxidative stress in the melanocytes," Dr. Ahmed said. A handout he provided to patients receiving UVB therapy includes recommendations for vitamin C, vitamin E, and alpha-lipoic acid supplementation.
Another controlled prospective study of 130 patients with vitiligo, also conducted in Italy, utilized a different antioxidant cocktail in a tablet – Phyllanthus emblica (known as Indian gooseberry), vitamin E, and carotenoids – taken three times a day, in conjunction with standard topical therapy and phototherapy. At 6 months, a significantly higher number of patients receiving the cocktail had mild repigmentation and were less likely to have no repigmentation compared with patients who did not receive the antioxidants. "Nobody did really great, but the cocktail group did a little better," he said. "So there's promise."
Vitamin D: In-vitro studies show that vitamin D may protect melanocytes against oxidative stress, and two small controlled trials showed improvement in vitiligo with vitamin D supplementation (1,500-5,000 IU daily) and no NB-UVB therapy. However, a recent, higher-quality 6-month trial that evaluated 5,000 IU/day of vitamin D in patients with generalized vitiligo showed no advantage over NB-UVB therapy alone. "I tell patients, if you're insufficient, take vitamin D (supplements) to get your levels up," Dr. Ahmed sad. "But if you're already sufficient, I'm not confident there will be a significant benefit."
Ginkgo biloba: A small double-blind controlled trial randomized 47 patients with limited and slow-spreading vitiligo to receive Ginkgo biloba extract 40 mg three times a day or placebo. At 6 months, 10 patients who received the extract had greater than 75% repigmentation compared with 2 patients in the placebo group. Patients receiving Ginkgo biloba, which has immunomodulatory and antioxidant properties, were also significantly more likely to have disease stabilization.
"I tend to recommend it to patients not doing phototherapy, as well as those receiving phototherapy, especially since the study showed benefit as a monotherapy," Dr. Ahmed said in an interview after the meeting.
Phenylalanine: Various oral and/or topical formulations of this amino acid and precursor to tyrosine/melanin have been shown to have repigmentation effects when combined with UVA phototherapy or sunlight, but the studies are of limited quality and the oral dosages studied (50 mg/kg per day to 100 mg/kg per day) appear to be a bit high, Dr. Ahmed said at the meeting. "It can add up in cost, and I worry a little about side effects, so I don't recommend it as much."
Polypodium leucotomos (PL): This plant extract, from a fern native to Central America and parts of South America, is familiar as a photoprotective supplement, he said, and a few randomized controlled trials show that it may improve repigmentation outcomes, especially on the hands and neck, when combined with NB-UVB in patients with vitiligo.
One of these trials, published in 2021, showed greater than 50% repigmentation at 6 months in 48% of patients with generalized vitiligo who received oral PL (480 mg twice a day) and NB-UVB, versus 22% in patients receiving NB-UVB alone. PL may be "reasonable to consider, though it can get a little pricey," he said.
Other supplements: Nigella sativa seed oil (black seed oil) and the Ayurvedic herb Picrorhiza kurroa (also known as kutki), have shown some promise and merit further study in vitiligo, Dr. Ahmed said. Data on vitamin B12 and folate are mixed, and there is no evidence of a helpful role of zinc for vitiligo, he noted at the meeting.
Overall, there is a "paucity of large, high-quality trials for [complementary] therapies for vitiligo," Dr. Ahmed said. "We need big randomized controlled trials ... and we need stratification. The problem is a lot of these studies don't stratify: Is the patient active or inactive, for instance? Do they have poliosis or not?" Also missing in many studies are data on safety and adverse events. "Is that because of an excellent safety profile or lack of scientific rigor? I don't know."
Future approaches to vitiligo management will likely integrate alternative/nutritional modalities with conventional medical treatments, newer targeted therapies, and surgery when necessary, he said. In the case of surgery, he referred to the June 2023 Food and Drug Administration approval of the RECELL Autologous Cell Harvesting Device for repigmentation of stable depigmented vitiligo lesions, an office-based grafting procedure.
The topical Janus kinase (JAK) inhibitor ruxolitinib (Opzelura) approved in 2022 for nonsegmental vitiligo, he said, produced "good, not great" results in two pivotal phase 3 trials . At 24 weeks, about 30% of patients on the treatment achieved at least a 75% improvement in the facial Vitiligo Area Scoring Index (F-VASI75), compared with about 10% of patients in the placebo groups.
Asked to comment on antioxidant pathways and the potential of complementary therapies for vitiligo, Jason Hawkes, MD, a dermatologist in Rocklin, Calif., who also spoke at the IDS meeting, said that oxidative stress is among the processes that may contribute to melanocyte degeneration seen in vitiligo.
The immunopathogenesis of vitiligo is "multilayered and complex," he said. "While the T lymphocyte plays a central role in this disease, there are other genetic and biologic processes [including oxidative stress] that also contribute to the destruction of melanocytes."
Reducing oxidative stress in the body and skin via supplements such as vitamin E, coenzyme Q10, and alpha-lipoic acid "may represent complementary treatments used for the treatment of vitiligo," said Dr. Hawkes. And as more is learned about the pathogenic role of oxidative stress and its impact on diseases of pigmentation, "therapeutic targeting of the antioxidation-related signaling pathways in the skin may represent a novel treatment for vitiligo or other related conditions."
Dr. Hawkes disclosed ties with AbbVie, Arcutis, Bristol-Myers Squibb, Boehringer Ingelheim, Janssen, LEO, Lilly, Novartis, Pfizer, Regeneron, Sanofi, Sun Pharma, and UCB. Dr. Hawkes disclosed serving as an investigator and advisory board member for Avita and an investigator for Pfizer.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
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Cite this: Dietary Supplements May Play a Role in Managing Vitiligo - Medscape - Nov 30, 2023.
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