Could your GLP-1 cause hair loss?

You may have heard about some of the side effects of GLP-1 medications — nausea, vomiting, you get the idea. But GLP-1 hair loss? Until recently, it’s flown under the radar. When you start a medication like Wegovy (semaglutide) or Zepbound (tirzepatide), you expect to lose weight. You don’t expect to lose strands in the process too. 

But there’s good news: Although hair loss is listed as a side effect for both Wegovy and Zepbound, the drugs don't appear to attack hair follicles directly, and the shedding is usually temporary. Here’s what’s actually going on, as well as when you can expect your hair to get back to normal. 

Key Takeaways

• Hair loss doesn’t seem to be caused directly by GLP-1s, but rather by the rapid weight loss GLP-1s can lead to.

• It’s usually temporary, unless you have an underlying hair issue happening.

• You can offset it by prioritizing protein, losing weight gradually, and getting nutrients like zinc and iron.

GLP-1s can lead to hair loss, but not because they mess with your hair follicles, or because the medication itself is doing anything to them. Rather, the uptick in shedding is typically “triggered by the metabolic shock of rapid change,” says Dr. Jessie Cheung, M.D., a board-certified dermatologist in New York, NY and Willowbrook, IL. 

The clinical term for this is telogen effluvium, says Cheung, and research shows it’s a primary hair-loss pattern reported with GLP-1 medication use.

A lot of things in life can trigger telogen effluvium. Childbirth (as with postpartum hair loss), a stressful life event like a divorce, and even menopause can contribute to it. Rapid weight loss — which generally means losing more than two pounds per week — is a big one. 

“When the body senses a major change in calorie intake, weight, or nutrient availability, it may divert resources away from processes it considers nonessential for survival — and hair growth falls into that category,” says Dr. Melanie Palm, M.D., a board-certified dermatologist in San Diego, CA. 

Telogen effluvium triggers more follicles than usual to shift out of the active growth phase and into the resting (or telogen) phase. Then, two to three months after that, they shed all at once, leading to more hair loss than usual. Because the actual hair loss occurs after the triggering event, “patients may not immediately connect it to the beginning of [their GLP-1] treatment,” says Palm. 

And it’s not just the weight loss alone. A lower appetite, which is pretty much how GLP-1s work, can also make the issue worse. “Some patients are simply not consuming enough protein, iron or other nutrients because they become full so quickly,” she says.

GLP-1 hair loss doesn’t always happen, though: “Someone can lose a substantial amount of weight and experience very little shedding, while another patient may notice significant hair loss after a more modest change,” says Palm. Hair follicles are very individual, she says — so there’s no way to predict whether or not you’ll lose hair. One clue, however, is whether you’ve experienced telogen effluvium in the past. Did you have intense postpartum hair loss, for example? Then your hair follicles might be more sensitive, and therefore more prone to shedding on a GLP-1, too.

If you have classic telogen effluvium — meaning there's nothing else going on that could contribute to hair loss — the GLP-1 hair loss won't be permanent. The shedding eases up once the trigger (such as rapid weight loss) is corrected.

“Once weight stabilizes and the body adapts, shedding typically begins to improve within three to six months,” says Cheung. “Most patients see noticeable regrowth over six to 12 months, although recovery depends on maintaining good nutrition and addressing any underlying deficiencies.” Not eating enough for your body weight, as well as deficiencies in nutrients like iron, can keep you in shedding mode indefinitely.

However, that’s based on the assumption that you’re only experiencing telogen effluvium. “If the shedding unmasks underlying androgenetic or pattern hair loss, the hair may not return completely without treatment,” says Palm. 

There are some hints. Telogen effluvium is more sudden than pattern hair loss, which develops gradually and follows a more recognizable distribution: Your center part widens, your ponytail feels thinner, and hair looks less dense at the crown. A derm can help you get to the bottom of it by looking at the pattern of thinning. "If the shedding improves but the density never fully returns, or the part continues to widen, that raises more concern for underlying pattern hair loss," says Palm.

Researchers still aren’t sure whether one GLP-1 medication leads to more hair loss than another. For example, one head-to-head trial comparing semaglutide and tirzepatide, SURMOUNT-5, found that alopecia in 8.3% of participants on tirzepatide versus 6.1% of participants on semaglutide. Placebo-controlled trials showed similar patterns: 5% of participants on 15mg of tirzepatide experienced alopecia compared with roughly 1% on placebo; 3% of participants on semaglutide experienced alopecia compared with roughly 1% on placebo. 

But FDA side effect reports —  known as FAERS pharmacovigilance — actually showed the opposite, that semaglutide was the GLP-1 that led to more alopecia. “Rather than assuming one particular drug automatically causes worse hair loss, I would say the risk may rise as weight loss becomes faster or more dramatic,” says Palm. 

Both men and women can experience GLP-1 hair loss. “I see more women coming in concerned about it, although that doesn’t necessarily prove women are biologically more susceptible,” says Palm. “Women tend to notice changes in hair density sooner, and hair shedding can be especially distressing when someone already has fine hair or female-pattern thinning.” 

In clinical trials printed on the manufacturer labels for both Wegovy (semaglutide) and Zepbound (tirzepatide), hair loss was more frequent in women. For example, for Wegovy at a weekly maintenance dose of 2.4mg, 4% of female participants reported alopecia compared with .9% of men. For Zepbound, at weekly maintenance doses 5-15mg, 7.1% of female participants reported hair loss vs. .5% of male participants.

That said, women do have other potential sources of hair loss, like low iron levels and perimenopausal changes, that could overlap with GLP-1. 

There’s really no way to avoid GLP-1 hair loss entirely, “but we can reduce avoidable stress on the follicle,” says Palm. “The biggest mistake I see is allowing appetite suppression to turn into nutritional deprivation.” She recommends working with your prescriber to determine a rate of weight loss that’s both sustainable and appropriate for your individual case, rather than trying to lose the most amount of weight quickly. 

That’s always the goal when you work with a Clinician through the Weight Watchers Med+ Program — to improve your health, using medication, nutrition, activity, and community as tools. Prefer to get your prescription elsewhere? You can still join the Weight Watchers GLP-1 Success Program to get a nutritional and lifestyle blueprint that’s designed to help minimize side effects. And for one-on-one nutrition, you can always book a virtual consultation with a Weight Watchers Registered Dietitian. No membership is required, and your appointment may even be covered by insurance.

To keep GLP-1 nutrition gaps from worsening shedding, keep these tips in mind:

Prioritize protein

The first order of business: Make sure you’re eating enough protein. After all, Palm points out, hair is primarily made of keratin, which is a protein — and if you’re only taking a few bites of each meal because you get full quickly, “patients taking GLP-1 medications can unintentionally fall far below their needs,” she says. “I generally encourage patients to build meals around a meaningful source of protein rather than hoping they will make it up at the end of the day.”

That doesn’t mean carbs and fats don’t have their place. Healthy fats, for their part, “provide essential fatty acids that support the skin and scalp,” says Palm. “A balanced diet is still preferable.”

Don’t lose weight too fast

It’s not just weight loss, but the speed of weight loss that can shock your body and inadvertently cause telogen effluvium, says Palm. That’s why GLP-1 hair loss has become more of an occurrence than with other ways of losing weight: It tends to lead to more rapid weight loss than other weight-loss medications out there. Being intentional about more gradual weight loss — ideally just .5 to 1% of body weight per week —  can help reduce the metabolic change in your body, in turn minimizing its impact on your hair follicles. 

Check key nutrients

If you are experiencing hair loss, Cheung likes to check for certain nutrients directly. “Both iron and zinc are common culprits in hair loss, and both are fixable once you know your numbers,” she says.

Iron helps with hair growth, but both experts recommend against supplementing it blindly. “The first step is determining whether the patient is iron deficient and looking at ferritin in the context of the rest of the laboratory work and clinical picture,” says Palm. A deficiency in zinc can contribute to hair loss as well. However, since excess zinc can interfere with copper absorption, “it should ideally be confirmed or strongly suspected before supplementation,” she says.

Other nutrients worth considering are vitamin D, vitamin B12, folate, and essential fatty acids, according to Palm. While biotin gets a ton of attention when it comes to hair health, a true deficiency isn’t that common. Plus, those super-high doses you might get over the counter have a drawback. “High-dose biotin can also interfere with certain laboratory tests, including thyroid and cardiac testing,” says Palm. 

When to see a doctor

If your shedding is severe (meaning you’re seeing bald spots), lasts more than six months, comes with scalp issues (like flakes or scaling), or is accompanied by a loss of eyebrows or body hair, then Palm recommends seeing a dermatologist. “Those features warrant a closer look rather than assuming everything is due to the GLP-1,” she says. 

If your shedding has slowed down and new growth is coming in, there’s not a lot to do to speed up the process. Minoxidil may be helpful when regrowth is moving very slowly, says Palm. The topical format is a good starting point, but low-dose oral minoxidil can also speed things up in the right patient. Palm recommends caution, though, since "it's an off-label medication and not appropriate for everyone.” Scalp injections using PRP (platelet-rich plasma) can also be beneficial, but only if your provider suspects underlying pattern hair loss, too.

GLP-1 hair loss is bound to come up when you’re talking about Ozempic, Wegovy, Zepbound, and Mounjaro side effects (along with other types of GLP-1s), in part because they can lead to dramatic weight loss. This shift can trigger telogen effluvium, which causes increased (but usually temporary) shedding that lasts for a few months. 

Even if it’s too late to lose weight at a more gradual pace, which can help minimize the risk of losing your hair, you can still encourage new growth by piling your plate with protein as well as hair-friendly nutrients like zinc and iron. Pairing your medication with Weight Watchers can help make sure you’re getting the nutrition and other healthy habits you need to truly feel (and look) your best on a GLP-1. Unless there’s more going on, your hair will eventually grow back — so you can enjoy the benefits of the weight loss alongside a full head of hair.