Dermatol Online J. 2010 Feb 15;16(2):3.

Does D matter? The role of vitamin D in hair disorders and hair follicle cycling.
Amor KT, et al

Conclusion
Extensive data from animal models clearly show that the VDR, independent of vitamin D3 hormone, plays an important role in the hair follicle cycle, specifically anagen initiation. Studies have demonstrated the ability of vitamin D3 analogs to stimulate hair regrowth, but clinical trials of calcitriol in humans have been unable to replicate these results. Reasons for this may be that more potent analogs of vitamin D3 were used in the animal studies than the human trials. Also, the mechanism of hair recovery in nude mice may not be applicable to humans with alopecia. The latter is reflected in one study that used nude mice with congenital alopecia, which does not have an equivalent in humans. This review shows the need for further exploration of the role of vitamin D and the VDR in the hair cycle. For clinical hair disorders in which there is an abnormal hair cycle, such as chemotherapy-induced alopecia, treatments that up regulate the expression of the vitamin D receptor may be successful. Developments of such treatments are a future area of study. Furthermore, studies on the optimal levels of local and systemic vitamin D levels are still limited and there is currently no evidence-based data to recommend vitamin D supplementation for various types of hair loss. In order to fully understand the effects of vitamin D supplementation in alopecia, future studies should compare results in vitamin D deficient patients to those in vitamin D sufficient patients.

Hair Loss Treatment at the proctor clinic. We treat hair loss