Protects: Because biotin strengthens hair, it is less likely to break off at the ends, promoting and protecting length, explains Friese. Although rare, pregnant women may become biotin deficient. To help promote baby health, take a prenatal vitamin that contains biotin and folic acid during pregnancy. High doses of biotin, however, can be dangerous to the baby, so additional supplementation of biotin isn’t recommended. Some people recommend biotin supplementation to aid hair growth. However, there is no clinical evidence to support its use for this purpose.

A limited number of reliable indicators of biotin status is available [ 7]. In healthy adults, the concentration of biotin is 133–329 pmol/L in serum and 18–127 nmol/24 hours in urine [ 2]. Abnormally low urinary excretion of biotin is an indicator of biotin deficiency, as is abnormally high excretion of 3-hydroxyisovaleric acid (higher than 3.3 mmol/mol creatinine) or 3-hydroxyisovalerylcarnitine (higher than 0.06 mmol/mol creatinine) resulting from reduced activity of MCC [ 2, 7, 8]. The most reliable individual markers of biotin status, including deficiency and sufficiency, are biotinylated MCC and propionyl-CoA carboxylase in white blood cells [ 7]. Oral administration of large doses of biotin increases serum concentrations of biotin and its metabolites [ 1, 9]. However, serum concentrations of biotin and its catabolites are not good indicators of marginal biotin deficiency because they do not decrease sufficiently in people with marginal biotin deficiency for these changes to be detectable with existing tests [ 3, 10]. Recommended Intakes Boccaletti V, Zendri E, Giordano G, Gnetti L, De Panfilis G. Familial Uncombable Hair Syndrome: Ultrastructural Hair Study and Response to Biotin. Pediatr Dermatol 2007;24:E14-6. [ PubMed abstract]Various other nutritional supplements could improve hair health. However, human trials have not supported the efficacy of many of these remedies for this purpose. Li D, Rooney MR, Burmeister LA, Basta NE, Lutsey PL. Trends in Daily Use of Biotin Supplements Among US Adults, 1999-2016. JAMA. 2020 Aug 11;324(6):605-7.

Sweet potatoes have 2.4 micrograms of biotin in half a cup, about 8% of your daily value of biotin.The answer to this one is ‘probably’ or ‘maybe’. I know it is not much of an answer, but there is as yet no definitive scientific evidence that it can help your hair to grow faster and more fully. Institute of Medicine. Dietary reference intakes: the essential guide to nutrient requirements . Washington, DC: National Academies Press; 2006. As mentioned above, biotin helps the regulate blood sugar, but that’s not all– it also helps lower the blood pressure of those suffering from diabetes. Those who have trouble maintaining their glucose levels may especially benefit from this. Frontiers in Nutrition: “Influence of biotin intervention on glycemic control and lipid profile in patients with type 2 diabetes mellitus: A systematic review and meta-analysis." If you want to get naturally occurring biotin, incorporate the following foods into your daily diet: