Biotin for hair growth: Can it help?

By Anna H. Chacon, MD, Fellow of the American Academy of Dermatology Jun 10, 2022 • 4 min

Biotin is an essential B vitamin that is found in certain foods and is available as a dietary supplement. Biotin is touted for its ability to help promote hair growth, and it’s a common ingredient in shampoos, conditioners and hair growth products. Here we take a look at biotin as a potential remedy for hair loss or thinning hair.

Does biotin help hair growth?

Biotin plays an important role in the production of keratin, the protein that makes up your hair. However, the evidence for this vitamin as a treatment for hair loss is limited. 

While some studies show taking biotin supplements or using hair products that contain biotin helped regrow hair, the studies were small, and the results are inconclusive. More research is needed to understand the potential benefits of biotin on hair growth.

Can biotin help prevent hair loss?

While the evidence for biotin as a hair-loss prevention treatment is stronger than it is for this vitamin as a hair-growth therapy, biotin supplements may only work for people who have a biotin deficiency to begin with. There’s no evidence to support claims that it helps nondeficient people regrow their hair or that it prevents hair loss. Still, it’s widely touted as a hair-loss remedy, and many brands of biotin supplements and products that contain biotin often advertise it as such. But products like biotin oil for hair and other topical biotin hair treatments generally don’t work, although there is no evidence that they cause harm.

How do you know if you have a biotin deficiency?

Biotin deficiency is rare, and no reports have ever identified a severe deficiency in a healthy person who eats a balanced diet. 

Signs of biotin deficiency include:

  • Thinning hair
  • Scaly, red rash around the eyes, nose and mouth
  • Seizures
  • Skin infections
  • Brittle nails
  • Mental issues like depression, hallucinations and lethargy

Risk factors for a biotin deficiency include:

  • Biotinidase deficiency, which is a genetic disorder that leaves the body unable to reuse and recycle biotin
  • Heavy alcohol use, which inhibits the absorption of biotin
  • A poor diet that leads to low levels of biotin and other nutrients
  • Inflammatory bowel diseases like ulcerative colitis and irritable bowel syndrome, which reduce the production of biotin in the gut
  • Pregnancy and breastfeeding, which may lead the body to increase its use of biotin or reduce absorption
  • Medications like retinoids and those used to treat seizure disorders may contribute to a biotin deficiency

Should you take a biotin supplement?

While biotin is water soluble and considered safe when consumed in supplement form, high levels of biotin in the blood can interfere with certain lab tests, so it’s important to tell your healthcare provider if you’re taking biotin supplements.

The adequate intake level of biotin for adults is considered to be 30 mcg daily. Most people get enough  biotin from their diet and don’t need supplements. Food sources of biotin include eggs, meat, fish, nuts, seeds and starchy vegetables like sweet potatoes. 

If you have symptoms of a biotin deficiency, or you’re experiencing unexplained hair loss, visit your healthcare provider. They can help you determine the cause and recommend an effective treatment to regrow hair or prevent further loss.

Published June 2022.

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