Primarily, biotin deficiency like other B-vitamin deficiencies, tends to show as a skin rash, as well as fatigue, depression, as well as peripheral neuropathy-like symptoms. Biotin deficiency can affect hair and skin health; such is the rationale for adding biotin to personal care products. This may be more severe in diabetics and alcoholics.

In diabetes, it may actually be that the need for biotin is greater than average. We also know that when diabetic patients are given biotin supplementation, along with the other B-vitamins, blood lipid and sugar profiles can improve.