Biotin Is the Internet's Favorite Fix for Hair Thinning—Experts Say It's Not So Simple

Want better hair? Use biotin. At least that's what the internet says. For years, biotin has been synonymous with good hair in the collective consciousness (much like retinol has been synonymous with youthful skin and vitamin C has been synonymous with a bright, even-toned complexion). Yet, despite its reputation, we have a sneaking suspicion that biotin is not wholly understood by everyone who uses it. How does it work? Are there any side effects? And does it really boost hair growth and thickness or is that a benefit that's been blown out of proportion?

These are critical questions to answer before investing hard-earned time and money in biotin hair products and supplements. That's why we tapped hair and scalp experts to get all of the nitty-gritty details. Ahead, learn everything you need to know about biotin for hair.

What Is Biotin?

"Biotin is thought to support the growth of hair, skin, and nails because it is involved in a variety of cellular functions and enzymatic reactions that help convert food into energy," says double board-certified dermatologist Brendan Camp, MD. In other words, there's good reason for the affiliation between biotin and hair growth. However, the experts are quick to caution us against thinking it's some kind of magical cure-all.

Benefits of Biotin

"Biotin is thought to support the growth of hair, skin, and nails because it is involved in a variety of cellular functions and enzymatic reactions that help convert food into energy," Camp says. In other words, there's good reason for the affiliation between biotin and hair growth. However, the experts are quick to caution us against thinking it's some kind of magical cure-all.

Can Biotin Really Boost Hair Growth?

The experts say using biotin for hair growth isn't always as helpful as the internet might lead you to believe. "Biotin deficiency, while uncommon, can be associated with hair loss," Camp says. "In those who are not biotin deficient, taking biotin as a supplement to support hair growth needs more research to conclusively support it as a hair growth treatment." In other words, the jury is out on whether biotin can substantially affect hair growth for most people. In fact, Camp says there is "limited evidence" to go on at all.

Board-certified cosmetic dermatologist Robert Finney, MD, agrees. "It’s true that biotin is essential for hair growth, amongst other things, but it's also true that biotin deficiency is extremely rare, especially in the U.S., and as a hair-loss expert, I still have yet to see a case where biotin deficiency is the cause,” he says. "The bacteria in our GI tracts actually produce biotin that we absorb, and it is found in many foods.”

Side Effects of Biotin

While biotin supplementation is generally considered to be safe, there are some potential side effects worth mentioning. First, many people claim that using biotin led to increased breakouts. Camp says the correlation isn't exactly unfounded. "There are some reports that biotin may contribute to acne formation, especially in those with acne-prone skin," he says.

Unfortunately, it seems to come down to good old trial and error. If using biotin leads to increased breakout activity, pare it back or stop it completely. If not, you're probably good to go. (As always, consulting a skincare expert like a dermatologist or aesthetician is your best bet when experiencing acne. They can help suss out the cause and provide you with the best treatments.)

Increased acne isn't the only potential side effect of biotin supplementation. Camp says it can affect the accuracy of certain medical tests. "Excess biotin supplementation may also alter the accuracy of lab studies done to evaluate for myocardial infarctions and thyroid function," he says. This potential interference is certainly something to consider before going all in on biotin supplementation. As always, we recommend consulting your doctor before using any new supplements.

If you don't want to mess with biotin supplements, you can always opt for biotin-spiked hair products. Experts maintain that topical delivery is generally thought to be safe, even if the efficacy is unclear. Still, many people are biotin loyalists, and they incorporate it into their daily beauty and wellness routines. If you're interested in trying out to see whether it affects your hair growth and thickness, keep scrolling to shop the best biotin products.

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