Nutrition and Hair: Deficiencies and Supplements

Interview by Andreas M. Finner MD,Dermatologic Clinics
Hair follicle cells have a high turnover. Their active metabolism requires a good supply of nutrients and energy. A caloric deprivation or deficiency of several components, such as proteins, minerals, essential fatty acids, and vitamins, caused by inborn errors or reduced uptake can lead to structural abnormalities, pigmentation changes, or hair loss, although exact data are often lacking. Combined deficiencies are not uncommon, especially in malnutrition.

In developed countries, hair growth disorders caused by nutritional deficiencies in healthy individuals are rare and tend to be overestimated by patients and physicians, especially concerning vitamins. National and International Institutions have established recommended daily allowances of many nutritional components. In the United States, the National Institutes of Health has published recommendations for the daily reference intake of micronutrients and macronutrients and the maximum daily intake that will likely not cause adverse effects. Dietary supplements have traditionally been used unspecifically to improve hair growth, a few of which have been studied systematically in animals and humans.