Nutritional supplements that may be helpful: Supplementation with the amino acid L-phenylalanine (LPA) may have value when combined with ultraviolet (UVA) light therapy. Several clinical trials, including one double-blind trial, indicated that LPA (50 mg per 2.2 pounds of body weight per day—3,500 mg per day for a 154-pound person—or less) increased the extent of repigmentation induced by UVA therapy. LPA alone also produced a more modest repigmentation in some people.² A study of vitiligo in children reported that LPA plus UVA was an effective treatment in a majority of the children.³

A group of Spanish doctors reported on their experience using LPA over a six-year period. Some of the 171 people with vitiligo received LPA (50 or 100 mg per 2.2 pounds body weight per day) for up to three years. Between April and October of each year, participants also applied a 10% LPA gel, prior to exposing their skin to the sun for 30 minutes. Some improvement was seen in 83% of participants, and the results were rated as good in 57% (75% improvement or better).⁴

A clinical report describes the use of vitamin supplements in the treatment of vitiligo.⁵ Folic acid and/or vitamin B12 and vitamin C levels were abnormally low in most of the 15 people studied. Supplementation with large amounts of folic acid (1–10 mg per day), along with vitamin C (1 gram per day) and intramuscular vitamin B12 injections (1,000 mcg every two weeks), produced marked repigmentation in eight people. These improvements became apparent after three months, but complete repigmentation required one to two years of continuous supplementation. In another study of people with vitiligo, oral supplementation with folic acid (10 mg per day) and vitamin B12 (2,000 mcg per day), combined with sun exposure, resulted in some repigmentation after three to six months in about half of the participants.⁶ This combined regimen was more effective than either vitamin supplementation or sun exposure alone.

When used topically in combination with sun exposure, a pharmaceutical form of vitamin D, called calcipotriol, may be effective in stimulating repigmentation in children with vitiligo. In a preliminary study, children applied a cream containing calcipotriol daily and exposed themselves to sunlight for 10–15 minutes the following morning.⁷ After 11 months, marked to complete repigmentation occurred in 55% of the children, moderate repigmentation occurred in 22%, and little or no improvement was seen in 22%. None of the children developed new areas of vitiligo. The first evidence of repigmentation occurred within 6 to 12 weeks in the majority of the children. All participants tolerated the cream well, with approximately 17% complaining of mild, transient skin irritation. Calcipotriol is a prescription medication to be used only under the supervision of a doctor. It is not known whether vitamin D as a dietary supplement has any effect on vitiligo.

In one early report, lack of stomach acid (achlorhydria) was associated with vitiligo. Supplementation with dilute hydrochloric acid after meals resulted in gradual repigmentation of the skin (after one year or more).⁸ Hydrochloric acid, or its more modern counterpart betaine HCl, should be taken only under the supervision of a doctor.

Another early report described the use of PABA (para-aminobenzoic acid)—a compound commonly found in B-complex vitamins—for vitiligo. Consistent use of 100 mg of PABA three or four times per day, along with an injectable form of PABA and a variety of hormones tailored to individual needs, resulted, in many cases, in repigmentation of areas affected by vitiligo.⁹