Do Hair Growth Supplements Really Work? I Got an Official Answer

Chloe Metzger
·11 min read
Photo credit: Katie Buckleitner
Photo credit: Katie Buckleitner

From Cosmopolitan

Spend even five minutes—nay, five seconds—on social media, and there’s a good chance you’ll be bombarded with pictures of influencers selling hair-growth supplements, ads for magical gummies promising to grow your hair faster and longer, and probably even your aunt swearing by some vitamin that gave her thicker, fuller hair overnight (and for the low, low price of a pyramid scheme!). And although I’m Cosmo’s resident skeptic—really, I could medal in party-pooping—even I have found myself drawn to the glowing allure of hair-growth pills.

Like, if everyone is taking them, they've gotta do something, right? And, hey, what's the harm in downing a gummy or a cute pill every day anyways?! (Uh, potentially a lot, but more on that below). Since I’m clearly not the only person having this internal crisis, I went ahead and chatted with a bunch of experts and dermatologists to find out whether hair vitamins actually grow your hair—and, even more important, whether they’re safe to take at all.

Photo credit: Getty Images
Photo credit: Getty Images

Will hair supplements actually grow my hair faster?

First, here’s what hair vitamins are allegedly supposed to do: revamp your hair from the inside out with a mix of “hair-friendly” ingredients, like biotin; folic acid; vitamins D, A, C, and E; and/or virtually anything else (!) they want to throw in there. Supplements and vitamins are not FDA-regulated, meaning brands can kinda say and do whatever they want. After a few months of taking them, your hair is supposed to look longer, healthier, shinier, and stronger, and your scalp’s oil production can speed up or slow down, depending on the formulation. At least, supposedly.

The thing is, these pills aren’t backed by government-approved data, and the research you can find on them are often...shady. "A lot of the studies you find in support of hair supplements are actually funded by the brands themselves," says Dhaval G. Bhanusali, dermatologist and founder of Hudson Dermatology and Laser Surgery in New York City. Bhanusali, who specializes in hair loss, says "the literature is sketchy at best, and most derms agree that supplements are not very impressive."

And because there isn’t really a uniform set of ingredients, strengths, or formulations across brands, there’s never going to be an official yes or no answer as to whether hair supplements work (and, more problematically, which formulations can mess with your body). But if you ask the experts—or me, who tried taking them for two months and was only left with zits—the answer is pretty much a big ol’ NOPE across the board.

Do hair growth vitamins work at all?

Okay, so even though vitamins themselves are absolutely necessary and beneficial for your hair, they won’t do much if your body is already stocked with them—which it probably already is. “Most people get all the vitamins they need to manage their hair growth just from their diet alone,” says trichologist Dominic Burg, chief scientist at Evolis Professional.

BUT shouldn’t I take them just in case?! I hear you ask. Sadly, more isn’t merrier here. Even if you ingest triple the vitamins your body needs (don’t), you won’t actually reap triple, or even double, the hair growth rewards. “Your body keeps only the vitamins it needs and then gets rid of the rest,” says Burg. Kind of like pouring water into a glass that’s already 100 percent full. So unless you’re actually missing some key nutrients, you’ll likely end up peeing out the excess pretty soon after you ingest them.

Photo credit: Getty Images
Photo credit: Getty Images

How do I know if vitamin deficiency is affecting my hair?

“There are a lot of women running around who are deficient and don’t realize it, because of either dieting, poor nutrition, or intense stress,” says Burg. And when you’re super stressed or not eating enough, “your body will shut down your hair growth first and redirect nutrients and energy to the organs that need it most,” he says, thus leaving you vitamin deficient.

And if you’ve ever experienced a severe bout of physical or emotional stress (hi, pandemic!), you might have noticed a sudden shedding of your hair a few months after (or, if not, congrats! You just figured out WTF was going on with your hair). “It’s a delayed reaction to the stress or diet that usually occurs three months later,” says Burg.

Of course, the only way to know for sure if your body is deficient is to have your levels tested by your doctor, so please don't start popping pills just because the entire world is a dumpster fire right now—instead, wait for a physician to tell you that. Duh.

How can I speed up hair growth if I’m healthy?

“There are some studies and anecdotal evidence that support the idea that low vitamin D levels can hinder hair growth, and a lot of people tend to have low vitamin D, even if they're otherwise healthy," says Dr. Bhanusali, noting the same for lower iron levels. "A lot of derms see good results by prescribing patients iron supplements and vitamin D supplements, though always check with your doctor before taking anything."

If you are not vitamin deficient (which, again, only a doctor can tell you), but still want longer, healthier, stronger hair, then sadly, “supplements will probably do very little for you,” says Burg. Hey, maybe you’ll be the lucky wild card—again, there are no mass studies definitively saying yes or no—but if we’re talkin’ from a point of science here, your odds aren’t great.

Not sure what to do? Talk to your doctor. Really. They can give you the thumbs up (or down) before you waste your money—or, worse, mess with your health.

Photo credit: Stocksy
Photo credit: Stocksy

How long do hair supplements take to work?

Regardless of whether you’re vitamin deficient or just a healthy person who somehow magically benefits from hair supplements, you still won’t see results overnight. Or even in a year. Or in five years. Why? “Your hair is dead, and nothing you do internally can affect its density, strength, or health,” says Burg. “Sure, vitamins will help the new hair that you’re growing, but because it grows only half an inch a month, it’ll take five or six years of taking supplements before a new strand of hair even reaches your shoulders.” Perspective, huh?

But that’s not to say you won’t see any changes before 2025. “If you’re vitamin deficient, supplements may help reactivate your oil glands after a few months, which can make your hair look shinier and more moisturized,” says Burg. And hey, you might even get the tiniest bit of additional hair growth, but that’s about it.

What about biotin—does it really help hair grow?

Sorry (again), but there's no definitive answer—yet a ton of doubt. According to dermatologist Vivian Bucay, MD, clinical assistant professor at the University of Texas Health Science Center, if you’re taking a stand-alone biotin supplement, you’d need to take at least 5 milligrams daily for it to have the chance of affecting hair growth—but even then, there’s no guarantee it’ll do anything.

Photo credit: Stocksy
Photo credit: Stocksy

It's also worth noting that biotin—just like any supplement—isn't without its downsides: Excess biotin has the potential to trigger breakouts in some acne-prone individuals (yup! Fun! We're having fun!). More research is needed to understand the exact correlation, but what is known is that taking biotin can also affect major medical tests your doctor may perform. Basically, unless you yourself are a doctor (which, hi, why you here?!), make sure to discuss all supplement-related info with an actual MD.

What are the best hair growth pills?

Okay, so let's pretend you’ve gotten your blood tested, you’ve gotten the green light from your doctor, you’ve made a deal with your god, and you’re ready to try some hair supplements. Cool. Do not go overboard. Doubling up on supplements can be incredibly dangerous over time—some vitamins get peed out by your system, but others can build up to toxic levels—so test only one supplement at a time, and make sure that whatever you ingest is a reputable, well-reviewed formula, like one of these best-selling pills.

How do I actually make my hair grow, then?!

Ah, yes, the question you should be asking: If not supplements, then what? Luckily, you've got a ton of options:

Minoxidil

Minoxidil is the active ingredient found in topical products like Rogaine and Hers. “We don’t know the exact mechanism for how it works, but we think a lot of it has to do with increasing blood flow to the scalp,” says Dr. Bhanusali. “It’s like giving more water to the plant to help it grow.” If you’re going to try minoxidil, you need to be consistent—use it every single day until…forever. And if you’re dealing with irritation, or you’re not seeing results after a few months, head to your derm for prescription options (more on that below).

Steroids

If your hair loss is rapid—i.e., you’re suddenly shedding a ton of hair—vs. gradual, there’s usually an underlying cause that should be addressed by a doctor or dermatologist ASAP. Topical steroids or steroid injections are often used as a short-term fix to help get the shedding under control, says. Dr. Bhanusali.

Spironolactone

Yup, the magical acne-clearing pill can also be helpful for hair growth. “Oral spironolactone is a prescription blood pressure medication that helps block androgens—male sex hormones—in females, which can help increase hair growth over time,” says Dr. Bhanusali. Another (off-label) added bonus? “Many patients find that their breakouts disappear, and their hair is less oily, too,” he says.

PRP therapy

Aka platelet-rich plasma therapy is a treatment where a doctor draws your blood, separates the plasma from it, then re-injects it into your scalp to help stimulate follicle activity. At least four sessions are usually required, aaaand it’s not cheap (think: $600-$1,200 per treatment). “I do think PRP can work in the right patient, but it’s not a guarantee,” says Dr. Bhanusali. “Studies generally show 20 percent of people get a significant improvement, 20 percent get slim-to-no results, and, anecdotally, the other 40 percent get maybe a 10-15 percent improvement.”

Compounded topicals

Historically, your only good hair-growth options were either a meh drugstore product at home, or a pricey treatment in the office. But the rise of skincare compounding (i.e., when your dermatologist custom-cocktails skincare formulas specifically for your face) has officially led to new options for your scalp, too—the latest of which is called HairStim.

“Your derm essentially evaluates your scalp and then can pick and choose whatever ingredients they think will help with hair growth, like higher-dose minoxidil, retinoic acid, finasteride, topical spiro, salicylic acid—whatever makes the most sense for the patient,” says Dr. Bhanusali. And, unlike other hair supplements or prescription products that doctors can sometimes get a kickback to recommend (yup!), “doctors don’t get a cent for recommending HairStim”—including Dr. Bhanusali himself, who helped create it. “It’s just another option for patients who aren’t finding success with OTC products, but don’t necessarily want to take medications or can’t afford more invasive treatments.”

FWIW, compound topicals aren’t usually covered by insurance. A HairStim formula, for example, costs about $60 and lasts between 30-60 days, depending on how much you’re applying and how big the "affected" area is (i.e., just your hairline vs. your entire head). “We usually see results between 10-12 weeks,” says Dr. Bhanusali.

And, hey, if it doesn’t work? You’ve got every other option in this article to consider—almost all of which will still give you better results than supplements. Sry not sry.

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