Vitamins and nail: In health and diseases.

Nails are specialized skin appendages. In addition to their physiologic, sensory, and protective functions, nails have great aesthetic appeal for women and men alike. Vitamins play an important enzymatic and catalytic role in the human body and are critical for its normal growth and functioning. Vitamin deficiencies can lead to nail manifestations, which can be recognized easily but are generally nonspecific. There is a lack of substantial and robust evidence for the role of vitamin supplementation in improving general nail health or improving the appearance of diseased nails. Biotin and vitamin E supplementation have been used in various nail disorders with variable outcomes. The use of injudicious nutritional and dietary supplements to achieve healthy nails is not uniformly beneficial and may be associated with many risks.