Inhaltsstoff-Glossar

Biotin

What Is Biotin?

Biotin is also known as vitamin B7 or vitamin H because, like other B vitamins, it was first discovered in yeast. However, the International Union of Pure and Applied Chemistry (IUPAC) recommends using the name biotin exclusively. A biotin deficiency may contribute to increased inflammatory activity in the body and premature biological aging. Individuals who regularly consume raw egg whites are at a particularly high risk of deficiency because the high avidin content inhibits the absorption of biotin in the intestine. Contrary to many advertising claims, there is currently insufficient scientific evidence to support significant positive effects of biotin supplementation on skin, hair, and nails.

Where Does Biotin Naturally Occur?

Biotin is found in small amounts in many foods. Particularly rich sources include yeast, chanterelle mushrooms, beef liver, and peanut butter. The World Health Organization (WHO) recommends a daily intake of 30 micrograms of biotin for adults. The German Nutrition Society (DGE) and the European Food Safety Authority (EFSA) recommend an adequate daily intake of 40 micrograms of biotin for healthy adults. The exact physiological requirement, however, is still unknown.

Presumably because biotin is present in foods only in relatively small amounts, the body recycles biotin efficiently. After biotin has fulfilled its function as a component of carboxylase enzymes involved in macronutrient metabolism, it is recovered through the coordinated action of several enzymes. Nevertheless, some biotin is excreted in the urine, making dietary intake essential. In cases of biotin deficiency, the body likely increases the expression of transport proteins that transfer biotin from the intestine into the bloodstream.

What Is the Primary Function of Biotin in the Body?

Biotin is an important cofactor for several enzymes—known as carboxylases—that are essential for the metabolism of glucose, amino acids, and fatty acids. It plays a crucial role in fatty acid synthesis and therefore also influences the metabolism of the immune system.

Another important function of biotin is its ability to regulate certain genes within the cell nucleus through epigenetic mechanisms. By binding to histones—large protein complexes around which DNA is wrapped—biotin can regulate the activity of genes involved in promoting inflammation. It does so by preventing the translation of genetic information into functional inflammatory signaling molecules such as TNF-alpha and various cytokines. For this reason, biotin possesses anti-inflammatory properties.

If biotin deficiency occurs, the expression of these inflammation-promoting genes increases. Consequently, biotin deficiency promotes inflammatory reactions through increased cytokine secretion and contributes to premature biological aging.

One reason why the exact biotin requirement is difficult to determine may be that biotin is also produced by bacteria belonging to the body's intestinal microbiota. Some bacterial species synthesize biotin themselves, while others require it for survival. Biotin can therefore influence the composition of the gut microbiome. A deficiency may contribute to microbial imbalance, promote the growth of less favorable bacterial species, and potentially lead to hair loss.

Benefits

Important cofactor for several enzymes
Plays a crucial role in fatty acid synthesis

What Are the Benefits of Biotin Supplementation?

Biotin is considered safe, even at doses up to 100 times higher than the amounts recommended by nutritional societies. In several studies, participants took between 10 mg and 50 mg of biotin orally each day for several months without experiencing harmful side effects.

The human intestine contains receptors capable of absorbing biotin in both the small and large intestine. At very high doses—which can only be achieved through supplementation—biotin additionally enters the body's cells via passive diffusion.

Particularly in situations where biotin deficiency is likely—such as alcoholism, certain medications, genetic factors, or the regular consumption of raw egg whites—biotin supplementation may help prevent deficiency. Clinical studies have shown that supplementation can stop hair loss caused by biotin deficiency.