Umm…why are my eyebrows so thin?

Why are my eyebrows so thin? Woman looking in mirror with tweezer

Feel like every time you look in the mirror you can’t help but mutter: why are my eyebrows so thin? Now that over-plucking is 10 to 20 years behind us, most of us want brows that look gorgeously full and even. But if you swear that your eyebrows are getting thinner and thinner by the day, it could be a hormone imbalance that’s doing it. Here’s which ones make it especially hard to get a nice set of brows—and what to do.

3 hormone imbalances that can make eyebrows oh-so thin

Why are my eyebrows so thin? Woman getting eyebrows filled in by makeup artist

Thyroid + thin eyebrows

If you’re hypothyroid, that means your thyroid hormone levels are lower than what’s ideal. Thyroid conditions are very common—even more common than most of us think. Because of the way many physicians test thyroid hormones, there are most likely a lot more women out there dealing with the symptoms but have been told their thyroid function is normal.

Thyroid hormones are ultra important. They affect just about every cell in your body. We count on these unsung heroes for energy and metabolism, growth, your circadian rhythm, sex hormones, and much more. With hypothyroidism, you might notice that your eyebrows retain their fullness from your nose to about halfway across your eye. But that last half to the outer third of your brow? That’s where you’ll see thinning. The good news is: with proper treatment (taking replacement thyroid hormones), you can regrow the hair in that area. The downside: it may take a couple of months from whenever you reach an optimal dose for your body and condition. (Which can take some trial and error with testing and re-testing your levels.)

Menopause + your brows

Hair growth and hormones are tied together forever. Estrogen and progesterone are two sex hormones that help your locks get longer and look more luscious. So, when progesterone and estrogen decline as you start to approach menopause, you might start to observe some real changes in both the hair on your head and your brows. One of those changes is an increase in dryness. The other? Shedding and loss.

With estrogen and progesterone at all-time lows, many women end up having androgen hormones, like testosterone, as their dominant hormone in menopause. Some of the testosterone in your body converts to dihydrotestosterone, or DHT. DHT is way more potent than testosterone. It also causes hair follicles to shrink—which leads to more hairs falling out. In menopause, hormone replacement therapy may help with hair loss and keep your eyebrows from getting super thin. In cases where testosterone and DHT levels are high, some healthcare providers may be open to prescribing finasteride or dutasteride. These medications can block the conversion of testosterone to DHT and help keep your hair out of the sink and where it belongs.

Cortisol + your brows

If thyroid hormone imbalances and menopause are common, then this one is even more of an issue. Cortisol’s a superpower of a hormone. You wouldn’t even be alive without it. But there’s a flip side to it, too. Whenever you’re stressed (always for most of us!), your body ramps up the release of this hormone. If you’re facing something dangerous, that’s a great thing. It means your body is ready to shut down some functions with a goal of survival.

Unfortunately, most of us walk around with chronically high cortisol levels from our hectic lifestyles. That takes a real toll on our bodies. When cortisol’s released, your body gets the message to get glucose to your muscles so you can out run the threat. With it, things that are associated with survival—like hair growth—get put on the back burner. Your hair follicles prematurely leave the growth phase and go into a resting phase before falling out. (This is called telogen effluvium.)

So what does stress-related eyebrow loss look like? Much like it does on your head. It’s diffuse—which means it’s an overall thinning, rather than one section or patch. One of the best things you can do for stress-related eyebrow loss is to find ways to reduce your stress response. Take deep breaths, do yoga, cut back on the caffeine, get enough sleep, and journal. Make sure to foster relationships in your life that leave you feeling good and calm yet energized—not depleted. It’s also worth taking a peek at your face products. Many facial cleansers contain sulfates. While sulfates might not affect your friend, they could affect you. That’s especially true if you have sensitive skin. Sodium lauryl sulfate in particular can lead to irritation in some people. If the irritation gets bad enough, it might be a player in your eyebrow thinning, as the products you use on your facial skin inevitably get on your eyebrows too.