Evidence for Supplemental Treatments in Androgenetic Alopecia

diffuse thinning over entire scalp not due to thyroid disease or iron deficiency.³⁴ After application of a 0.1% melatonin or placebo solution, anagen hair rate was significantly increased in the occipital region of 12 women with FPHL and in the frontal region of 28 women with diffuse alopecia when compared to placebo (P<0.001). Although not statistically significant, the anagen hair phase was also increased in the frontal region of patients with FPHL and in the occipital region of patients with diffuse alopecia. Measured blood levels of melatonin showed increased levels but these levels were not beyond the physiological night peak. This was the first placebo- controlled study to demonstrate the efficacy and tolerability of melatonin in FPHL or AGA treatment and suggests its potential benefit to be attributed to induction of the anagen phase.

There are two products that each have a proprietary blend including a marine extract: Hairgain and Viviscal. A compound containing a marine extract was initially shown to be beneficial in brittle hair and nail therapy, which has led to investigations evaluating its effects in AGA and FPHL. A double blind placebo-controlled study of sixty patients comprised of 55 men and 5 women, 56 of whom had AGA, was performed using a dietary supplement with a marine protein extract (Hairgain^®) for six months followed by open-label extension for another six months.³⁵ Clinical response was evaluated using investigator assessments based on internationally accepted scales, close-up photographs, and subject assessments based on a 10 point Visual Analog Scale (VAS). Hair counting in close-up photographs demonstrated 32.4% increase in hair growth in the treatment group and insignificant change in the placebo group after six months. By the end of 12 months, an average hair growth of 63.9% was observed. The group initially receiving placebo experienced 60.8% increase in hair growth. This suggests continued improvement with continued treatment exposure. The VAS scores were also significantly higher in the treatment group compared to the placebo group (P<0.001). No serious side effects were reported by the end of the study. The mechanism of action for this supplement is unknown. Further studies are needed to evaluate the effect of treatment discontinuation with response maintenance. Furthermore, 55 of the 60 patients were men, which limits the generalizability of the results to the female population.

To better assess the efficacy of a marine extract supplement among females, a double-blind placebo controlled study was conducted using another marine protein extract (Viviscal^®) for 180 days among 15 women with self-perceived hair thinning.³⁶ Clinical assessments were based on close-up photographs of designated 4 cm² region and self-assessment questionnaires. The mean number of terminal hairs in the target region increased from 271.0 at baseline to 571 after 90 days and 609.6 after 180 days which was significantly higher than the placebo treated group with P<0.001. In self-assessment questionnaires, significantly more subjects in the treatment group reported increased hair volume after 90 days. After 180 days, patients also reported enhanced hair shine and skin smoothness. No adverse events occurred with treatment. Thus, this study supports the efficacy and tolerability of this marine extract supplement among females, although not specifically for those with FPHL. While these two studies suggest that marine protein extract may be helpful in hair loss, information on whether they contain the same marine protein extract is not available since these are proprietary formulas.

Zinc is crucial for proper enzyme functioning and its deficiency is also associated with alopecia.^37,38 In one case report, a child whose hair loss was attributed to zinc deficiency no longer experienced hair loss progression with zinc supplementation.³⁹ Serum zinc levels were assessed in patients with AGA, FPHL, alopecia areata, and telogen effluvium and were found to be significantly lower in all groups as compared to the control group, but were lowest in those with alopecia areata and telogen effluvium, so the role of zinc deficiency in AGA and FPHL is unclear.⁴⁰ In a randomized, double-blinded study of 200 men with type III and type IV AGA, the efficacy of 1% pyrithione zinc shampoo, 5% minoxidil topical solution, and a combination of the two treatments were compared to placebo treatment.⁴¹ Subjects and investigators rated their hair growth based on photographic depictions. After 9 weeks, all treatment groups demonstrated a significant increase in hair count as compared to placebo (P<0.05). Increase in hair count for the 1% pyrithione zinc shampoo was slightly less than half that for the 5% minoxidil solution. No increase in hair count was observed with the combination treatment versus the 5% minoxidil solution. In addition, the increase in hair count by pyrithione zinc shampoo use was only appreciated by the investigators. Thus, daily use of 1% pyrithione zinc shampoo may induce some improvement in AGA, although not comparable to minoxidil treatment, and possibly not cosmetically acceptable. It is possible that pyrithione zinc shampoo improved mild hair loss related to seborrheic dermatitis. Furthermore, this study provides no information on the efficacy of pyrithione zinc shampoo for the treatment of FPHL. Longer and larger clinical trials are needed to better assess the safety and efficacy of this treatment.

While oral zinc supplementation has been found to be helpful in some cases of telogen effluvium and zinc-deficiency related hair loss, no studies have been done on AGA or FPHL.

The challenge of cosmetically acceptable and complete medical treatments for AGA and FPHL often leads patients and physicians to seek alternative therapies. Among these treatments, randomized placebo-controlled studies are only available for melatonin treatments, two marine extract protein dietary supplements, and a pyrithione zinc shampoo. However, to date only one study has compared pyrithione zinc to currently FDA approved treatments. Limitations in hair research include length of treatment and study periods, difficulty in assessing response, and phenotypic diversity, which may lead to variability in treatment response. Thus, while patients and clinicians may choose to supplement