Does biotin really work for hair growth?

Does biotin ensure healthy skin, shiny hair and strong nails?

What's behind the biotin advertisement?

Some manufacturers call biotin "vitamin H" to emphasize its importance for skin and hair. This was the previous name when the vitamin and its effects on the skin were discovered in 1898. Manufacturers of dietary supplements advertise to this day with slogans such as: "For the healthy growth of strong nails, hair and skin".

The European Food Safety Authority (EFSA) has also assessed two health-related advertising claims as proven: "Biotin contributes to the maintenance of normal skin" and "Biotin contributes to the maintenance of normal hair". These have been approved by the EU with Regulation (EU) 432/2012.

Nevertheless, "beauty pills for skin, hair and nails" are offered, which refer to these health claims, but the wording is sometimes changed. For example, "For beautiful, healthy and strong hair" is advertised.

In contrast to skin and hair, a statement about the effect of biotin on the nails is not permitted. Older veterinary studies showed that biotin led to the hardening of the hooves in farm animals. That is why it has also been experimentally tested for the treatment of brittle or splintering nails as well as brittle and falling hair in humans. After high doses of biotin (2.5 mg / day), the nail thickness increased and the nail surface also improved. However, there are still no clinical studies that scientifically prove the effect on humans.

The EU has therefore not approved any advertising claims on biotin and nails. However, many dietary supplements are offered in combination with zinc or selenium, but also with silica. For zinc and selenium, a statement about "normal" nails is permitted and advertising on the product is permitted, but it must refer to these nutrients.

The fact that health-related statements about biotin are permitted does not mean, however, that biotin preparations are a useful addition to the menu. The EFSA points out that the biotin intake in the population is sufficient. Thus, no further effects on skin or hair are to be expected from an additional intake.

The situation is different when biotin is sold as a medicinal product. An effect must be proven for the high-dose drugs. The 5 milligram (mg) or 10 mg pills help with a clinically proven biotin deficiency or a hereditary metabolic disease (multiple carboxylase deficiency).

Following an evaluation by the EFSA, the European Union has approved further health-related claims, as biotin is involved in many metabolic processes:

  • contributes to the maintenance of normal mucous membranes
  • contributes to the normal functioning of the nervous system
  • contributes to normal psychological function
  • contributes to the normal metabolism of macronutrients
  • contributes to a normal energy metabolism

Biotin is therefore also a component of dietary supplements that promote intestinal health, the strengthening of the immune system or a balancing effect on the nervous system.

What should I look out for when using biotin products?

So far, no negative health consequences of increased biotin intake (up to 20 mg / day) are known, neither through food nor through high-dose drugs. There is therefore no fixed upper limit for the intake of biotin. Nevertheless, according to the Federal Institute for Risk Assessment (BfR), it cannot be concluded from this that these substances have no potential for undesirable effects. It recommends that dietary supplements containing biotin should always have a label stating that people who are required to undergo a laboratory test should inform laboratory staff that they are taking or have recently taken biotin.

Very important: Ingesting biotin falsifies laboratory tests. This can lead to both false positive and false negative results. This particularly affects examinations of thyroid hormones, sex hormones and cardiovascular markers such as troponin (in heart attacks). If you are taking a biotin-containing dietary supplement, it is essential that you report this when you take your blood sample.

What does the body need biotin for?

Biotin, formerly called vitamin B7, is a component of enzymes. It is involved in many metabolic processes such as carbohydrate, protein and fat metabolism and is involved in cell growth as well as in DNA and protein synthesis. In addition, biotin activates the metabolism and promotes the formation of new hair roots and the nail bed. The vitamin is soluble in water and is broken down by the body and most of it is excreted in the urine or stool.

High alcohol consumption, smoking and the use of certain medications to prevent epileptic seizures (anticonvulsants) impair the absorption of biotin or promote the breakdown of biotin. Nevertheless, a diet-related biotin deficiency is only described in exceptional situations such as artificial nutrition, the consumption of many raw eggs (avidin) or alcohol dependence. The risk of a deficiency also exists in people with congenitally impaired biotin utilization.

The skin is the most sensitive. A clinically pronounced deficiency is therefore expressed in hair loss, inflammation of the corner of the mouth, changes in the skin and mucous membranes. Muscle pain and specific psychiatric symptoms can occur later.

According to the BfR, pregnant women are possibly a risk group for a biotin deficiency, as it has been found that during pregnancy, more certain acids can be excreted in the urine. It can be a sign of a deficiency situation and, if left untreated, lead to health problems for the unborn child. The recommendations of the gynecologist therefore apply to pregnant women.

Can I cover my daily requirement with food?

Biotin, which is widespread in food, occurs both bound to proteins (animal foods) and in free form (plant foods).

The average amount of 40 micrograms of biotin consumed per day with normal eating habits is considered sufficient. Some indications also speak in favor of a synthesis of biotin by the intestinal flora and from the metabolism. Nevertheless, the daily requirement in humans can only be estimated to this day; it is not known exactly how much biotin the body needs.

The German Nutrition Society (DGE) estimates the appropriate daily intake at 40 micrograms for adults (including pregnant women), 45 micrograms for breastfeeding women and 35 micrograms for adolescents aged 15 and over. Age-dependent lower values ​​are given for children.

If you want to do something good for your skin and hair, eat a balanced diet with plenty of vegetables and fruits as well as whole grain products. Biotin is naturally found in oatmeal, wheat germ, eggs (heated), mushrooms and many other foods. Exercise outside, enough sleep and enough fluids in the form of water or unsweetened tea do the rest. In addition, you should use cleaning agents with gloves. The products often contain substances that can damage the nail.


German Nutrition Society: Biotin - Estimated Values ​​for Appropriate Intake. Reference values ​​for nutrient intake, 2nd edition, 6th updated edition 2020 (accessed on December 16, 2020)

German Nutrition Society: Selected questions and answers about biotin. Status: November 2020

BfR (2021): Updated maximum quantity proposals for vitamins and minerals in food supplements and fortified foods
Opinion No. 009/2021 of March 15, 2021

BfR (2021): Maximum amount proposals for biotin in food including food supplements

Ezeker H; Stahl A (2009): Biotin: Occurrence, functions, physiology, reference values ​​and supply in Germany, Ernahrung Umschau (5): 288-93 (accessed on December 16, 2020)

Mock DM (1991): Skin manifestations of biotin deficiency. Semin Dermatol 10 (4): 296-302. (accessed on December 16, 2020)

Huschka C (1998): Studies on the effect of biotin on human keratinocytes and on the modulation of biotin penetration in human skin, (accessed on December 16, 2020)

EFSA (2010): Scientific Opinion on the substantiation of health claims related to biotin and maintenance of normal skin and mucous membranes (ID 121), maintenance of normal hair (ID 121) […]. EFSA Journal 8 (10): 1728. (accessed on December 16, 2020)

EFSA (2014): Scientific Opinion on Dietary Reference Values ​​for biotin. EFSA Journal 2014; 12 (2); 3580 (accessed: December 16, 2020)

Reinke C (2004): Biotin (Vitamin H) Important for the health of hair and nails. Nutritional medicine (3): 23-7 (accessed on December 16, 2020)

Too little known and sometimes with serious consequences - laboratory tests falsified by biotin. arznei-telegram 50 (1): 14, 2019 (accessed on December 16, 2020)

Federal Institute for Risk Assessment: Biotin in food supplements can influence laboratory test results. Communication No. 044/2019 of November 14, 2019 (accessed on December 16, 2020)