You don’t have to go through life brow-less.

Thick, luxurious eyebrows are a signifier of youth, not to mention a keen awareness of fashion trends (see full browed beauties such as Lorde, Cara Delevigne). But while framing the windows to our soul seems effortless in the early decades of life, our brows thin as we age. The technical term for eyebrow hair loss is “madarosis,” which is fitting, because losing our brows can be absolutely maddening. British actress Saoirse Ronan, who had to bleach her brows into invisibility for a role, sums up the feeling: “If you don't have eyebrows, you don't really have a face.”

In order to restore brows to their prepubescent splendor, it’s key to pinpoint the cause of their demise. Eyebrow thinning and loss can be caused by a number of factors. Check out this list to see which issue is yours.

Overplucking: The brow goes all the way across the eye, but is very thin.

Hypothyroidism: The brow is missing its outer third (also called “Hertoghe” or “Queen Anne’s Sign.”) This can sometimes also happen as a result of the autoimmune disease lupus.

Nutrition: The loss or noticeable thinning of the entire brow can result from chronic zinc or iron deficiency.

Medication: Brows can also thin as a result of drugs—not just chemotherapy, but also common therapies such as retinoids, blood thinners, anti-cholesterol drugs and even mouthwash containing boric acid.

Behavior: Trichotillomania is a psychological condition which compels people to tug on hairs, pulling them out and damaging follicles.

There are many treatments and camouflages for eyebrow thinning and loss. If you have a tendency to overpluck, throw away your tweezers; if you must trim an unruly hair, instead of plucking, just use one of the tiny razors used by child beauty queens. This way, you’re leaving your follicles alone to heal. (Buy a sophisticated Japanese stainless steel mini-razor from Sephora here.)

People whose eyebrow loss pattern seems to indicate hypothyroidism or lupus should consult an endocrinologist. The outer third of brows will likely regrow with proper medical treatment. Those concerned their brow loss might be due to nutrition or medication issues should also see a doctor in order to pinpoint the cause of the problem, and make diet and prescription changes accordingly. If you suspect you’ve been unconsciously yanking on your brow hairs, consult a psychiatrist or cognitive behavioral therapist, who may be able to suggest medications or behavioral strategies that will help you give yourself a break. 

Thankfully, there’s a wide range of camouflage and treatment options to try once you’re on the road to eyebrow wellness. Sparse brows can be filled in with pencil, gel, or even permanent tattooing. Some dermatologists suggest off-label uses of two popular hair regrowth products—scalp tonic Minoxidil, and eyelash potion Latisse—twice a day, applied with a clean mascara wand (be careful not to drip!). And cosmetics companies have come out with targeted treatments, which aim both to enhance brows, and regrow them (Try Neubrow, Talika Eyebrow Lipocils, or Anastasia Brow Enhancing Serum). Finally, when all else fails, some hair restoration specialists are trying follicle transplants, moving hair from the nuchal ridge (the part of the scalp that meets the neck) to above the eyes. Just don’t forget to schedule frequent trims.