You’re putting on your makeup, and you notice that the outer edge of your eyebrows are thinner than usual. Your first instinct is probably to pull out an eyebrow pencil, and fill in the sparse area.
But if you notice that your eyebrows have thinned, and in particular, if the outer edge of the eyebrows have thinned — or even disappeared — that’s a sign that it’s time to have your thyroid checked.
This loss of hair in the outer edge of the brows is one of the very unique signs that point specifically to an underactive thyroid – known as hypothyroidism.
But any old thyroid check will not do. It’s not enough to just have the standard Thyroid Stimulating Hormone (TSH) test. At minimum, you will want to check TSH, Free Thyroxine (Free T4), Free Triiodothyronine (Free T3), Thyroid Peroxidase Antibodies (TPO), and Ferritin levels – you can download a free thyroid lab slip here.
Results need to be interpreted by an integrative physician or practitioner who is knowledgeable about hormone balance – here are a few resources for finding a good thyroid doctor.
If you are clinically or even subclinically hypothyroid — or you have evidence of Hashimoto’s disease, which is often picked up by elevated TPO antibodies — you may have this eyebrow thinning or eyebrow loss as a symptom – you can download a thyroid symptom checklist here.
Once you are properly diagnosed, treated, and optimized, it’s likely that your eyebrows will slowly grow back in. (But be patient — it can take months to see results!)