Originally published May 2018. Reviewed and substantially revised August 2026. Your genetics decide your eye colour and your height. They also influence how your body processes medications — which is part of why one person does well on a particular antidepressant while another feels awful on the same dose, and why some people tolerate a statin while others get muscle … Read More
Thyroid Test Results Explained: What TSH, T4 and T3 Mean
Originally published November 2017. Reviewed and rewritten August 2026 to reflect current guidance from the American Thyroid Association, AACE and AAFP. You had blood drawn, the result says “TSH,” and you have no idea what you’re looking at. Let’s fix that. What TSH actually is Your thyroid — the butterfly-shaped gland at the base of your neck — makes two … Read More