The thyroid is a small, butterfly-shaped gland located at the base of your neck. It may be tiny, but don’t underestimate its power. This little gland produces hormones primarily thyroxine (T4) and triiodothyronine (T3) which regulate the body's metabolism. Essentially, the thyroid is like the thermostat of your body, managing your energy usage, heartbeat, body temperature, and more.