Biotin for Hair Growth: Everything You Need to Know

biotin for hair

@aysha.sow & @alxcext /Design by Dion Mills

We've all seen it on our feeds: An influencer with an impossibly thick and shiny head of hair, who took to the caption to attribute their enviable locks to a bottle of biotin supplements.

Over the last few years, biotin has exploded in popularity, sought after for its purported ability to boost the health of nails, skin, and of course, hair. As with many things on social media, however, the reality of the situation is not so simple. While biotin—a member of the vitamin B family—is an important part of a balanced diet (and, as such, plays a role in hair health), there is not sufficient evidence to back the use of biotin supplements in those without deficiencies.

We spoke to BosleyMD certified trichologist Gretchen Friese and Angela Phipps, DO, ABHRS, medical advisor to HairClub, to learn more about what biotin can—and can not—do for your hair. Read on for what they had to say.

Meet the Expert

Biotin for Hair

Type of ingredient: A water-soluble vitamin that’s a part of the vitamin B family

Main benefits: Can improve hair health—including shine, volume, and scalp coverage—says Friese.

Who should use it: While there is some research to suggest increased biotin can improve hair strength, there is little proven data to support biotin supplementation for hair regrowth. Those experiencing hair loss should consult with a hair loss specialist instead.

How often can you use it: "Increasing your biotin intake between 2 mg and 5 mg per day may improve the strength and thickness of your hair," says Friese.

Don’t use with: "Most people can take biotin supplements without any negative effects, but minor side effects are possible," says Phipps, including nausea, diarrhea, and cramping.


Benefits of Biotin For Hair

Biotin, also known as vitamin B-7, is an essential nutrient that is most often found naturally in food; biotin-rich foods include cereals (wheat and oats), vegetables (like spinach and mushrooms), and rice. "Biotin converts glucose from carbohydrates into energy for the body and aids amino acids in carrying out normal bodily functions," says Phipps.

For anyone on Instagram, however, biotin is perhaps most famous for its purported ability to pump up hair and nails. Biotin "is well known for its positive effects on hair including growing stronger thicker strands," says Friese. "Stronger hair is less likely to break off at the ends, promoting and protecting length."

Phipps says that biotin improves the infrastructure of keratin, a basic protein that makes up hair, skin, and nails, "but beyond that, researchers aren’t really sure what biotin’s role in hair or skincare is. There is some research to suggest that increased biotin intake can improve overall hair quality, including thickness and shine."

Emphasis on the "some," however. While biotin plays a role in healthy hair, skin, and nails, the efficacy of biotin supplementation—beyond the biotin you get from simply eating a balanced and nutritious diet—is up for debate. "If you aren’t getting enough biotin, you may experience hair loss," says Phipps. "However, a deficiency is rare. In most cases, the biotin you get from your diet is enough for you to reap the health benefits it offers."

"Research on the effects of biotin on hair growth is insufficient in my opinion," she continues. "To date, there’s only limited evidence to suggest that increased biotin intake may help promote hair growth. In reviewing studies, evidence is inconclusive that biotin influences hair growth as supplements taken contain not only biotin but other ingredients as well. The improvement in hair growth cannot be attributed to the biotin alone."

Who Should Use Biotin for Hair Health?

While biotin can potentially make strands stronger and shinier, Phipps says that there isn't much proven scientific data to suggest that biotin supplementation can help with hair regrowth. "If you’re experiencing hair thinning or hair loss, it is best to see a hair loss specialist."

Making sure you're getting enough biotin in your diet, however, can potentially help prevent thinning in the first place. (Though again, deficiencies are pretty rare.) "Biotin can help maintain the health of your nervous system, which is important for healthy hair growth and prevention of hair loss," says Friese. "It can also fight inflammation."

"Although more research is needed to assess its effects on hair growth, biotin does have several proven benefits," adds Phipps. "For example, biotin is one of several B vitamins that support a healthy metabolism."

How to Use Biotin for Hair

While most people can take biotin supplements without any adverse reactions, Phipps says that it's best to pay a visit to your doctor before adding any supplements to your daily routine. "You may already be getting the biotin you need through your diet, so talk with your doctor about the best option for you. They may recommend certain dietary changes or a biotin supplement. Be sure to follow any dosage guidelines that they provide."

"When we aren’t getting all of our vitamins from the foods we eat is when we need to take supplements," adds Friese. "You can maintain a healthy biotin level by eating meat, eggs, fish, seeds, nuts, and some vegetables like spinach, broccoli, and sweet potatoes."

If your doctor gives you the green light for supplements, you can find pure biotin at most drug stores and almost all vitamin stores. Phipps says it's crucial to read all the fine print. "Although the Food and Drug Administration regulates dietary supplements, it’s important to read the packaging carefully and only purchase from a supplier you trust." And make sure to follow the doctor's orders: "If you’re taking a supplement, it’s important that you take it daily or as your doctor instructs you to."

Phipps notes that while most people can take biotin without any negative side effects, some people may experience nausea, cramping, or diarrhea. (Though "You may be able to reduce your risk for side effects by taking your supplement with food," she says.) If you have any unusual symptoms while taking a supplement, stop using it immediately and be sure to make an appointment with your doctor ASAP.

Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
  1. Patel DP, Swink SM, Castelo-Soccio L. A review of the use of biotin for hair lossSkin Appendage Disord. 2017;3(3):166-169.

  2. Saleem F, Soos MP. Biotin Deficiency. In: StatPearls. Treasure Island (FL): StatPearls Publishing; April 14, 2021.

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