Does it really boost hair, skin, and nail health?
By Densie Webb, PhD, RD
Biotin, also known as vitamin B7 or vitamin H (the H comes from Haar und Haut, German for hair and skin), is a water-soluble vitamin that’s an essential cofactor for metabolism of fatty acids and amino acids, and for the synthesis of glucose from fatty acids and amino acids. But it’s popularly known as a treatment for hair loss and as a way to strengthen nails and improve skin. While there are any number of supplements with names such as Hair Boost, Biotin Beauty Blend, and Hair, Skin & Nails, which leave no doubt as to what they’re formulated for, what are the facts about biotin?
Biotin Research
In the 1980s, biotin supplementation was recommended by the American Academy of Dermatology for hair loss in children.1 But this recommendation was mainly based on case studies and a 1989 German study with dogs, which found significant resolution of hair and skin conditions in 60% of the dogs that were treated with 5 mg biotin/10 kg body weight daily for three to six weeks.2 However, those findings haven’t been backed up by any clinical studies and biotin supplementation is no longer routinely recommended for unexplained hair loss. “There is limited current research on the use of biotin supplements for hair, skin, and nails,” says Yasi Ansari, MS, RDN, CSSD, a Los Angeles–based dietitian specializing in sports nutrition, wellness, and eating disorders and a national spokesperson for the Academy of Nutrition and Dietetics.
Biotin Deficiency
While no clinical studies show that biotin supplements will improve hair, skin, and nails in healthy individuals, supplementation is effective at treating hair loss in people with a biotin deficiency, which is rare. In fact, severe biotin deficiency in healthy individuals eating a normal, balanced diet has never been reported.3 Signs of clinical biotin deficiency include skin rashes, hair loss, and brittle nails, which is why biotin supplements are touted for hair, skin, and nails in healthy people.
“I often get asked about biotin supplementation and hair growth,” Ansari says. “There’s a lot of information out there—fun and fancy labels advertising the benefits of supplements for hair and skin, and there are people on social media with large followings sharing their positive experiences and marketing certain supplements. It’s understandable why people want to try new products that they think may help.”
While there’s no solid evidence that biotin supplements are needed in healthy people, biotin deficiency can occur in certain instances. Biotinidase deficiency is a rare genetic disorder that prevents the body from metabolizing biotin. Because it can be deadly, newborns are screened for the disorder. Alcohol interferes with biotin absorption, and about 15% of individuals with chronic alcoholism experience biotin deficiency.3 Raw egg whites contain avidin, a protein that binds biotin and renders it unavailable, so excessive intake of raw egg whites also can result in a biotin deficiency. In addition, long-term anticonvulsant therapy has been shown to impair biotin metabolism, but the clinical effects of reduced blood levels of biotin are unclear.4
Sources of Biotin
Biotin is available in many dietary supplements as a single nutrient or in combinations of other nutrients, mostly B-complex vitamins. Levels of biotin in supplements can be as high as 5,000 mcg, more than 160 times the Adequate Intake set by the National Academy of Sciences. While such high intake is unnecessary, there’s no evidence that it’s harmful.3 The recommended intake for biotin is 30 mcg/day for men and women older than 19, while a recommendation of 35 mcg/day has been set for breast-feeding women.
If a client or patient wants to supplement, Ansari recommends choosing a biotin supplement that has third-party certification. However, she stresses “the power of food” to her clients and says it’s important to remind them that foods contain a variety of vitamins, minerals, antioxidants, and macronutrients that support health. Some of the richest dietary sources of biotin include beef liver, eggs, salmon, pork chops, hamburger patties, sunflower seeds, and sweet potatoes. Lesser amounts are found in almonds, tuna, spinach, broccoli, cheddar cheese, milk, and yogurt.
— Densie Webb, PhD, RD, is a freelance writer, editor, and industry consultant based in Austin, Texas.
References
1. Soleymani T, Lo Sicco K, Shapiro J. The infatuation with biotin supplementation: is there truth behind its rising popularity? A comparative analysis of clinical efficacy versus social popularity. J Drugs Dermatol. 2017;16(5):496-500.
2. Frigg M, Schulze J, Völker L. Clinical study on the effect of biotin on skin conditions in dogs. Schweiz Arch Tierheilk. 1989;131(10):621-625.
3. Biotin: fact sheet for health professionals. National Institutes of Health, Office of Dietary Supplements website. https://ods.od.nih.gov/factsheets/Biotin-HealthProfessional/. Updated January 10, 2022. Accessed May 18, 2022.
4. Mock DM, Mock NI, Nelson RP, Lombard K. Disturbances in biotin metabolism in children undergoing long-term anticonvulsant therapy. J Pediatr Gastr Nutr. 1998;26(3):245-250.
