The thyroid gland is a small, butterfly-shaped gland in the front of your neck. Its hormones travel from the thyroid gland through the blood to all parts of the body. Thyroid hormones help all your organs to work well and control how your body uses food for energy. These hormones affect your metabolism rate, which means how slow or fast your brain, heart, muscles, liver and other parts of your body works. If your body works too fast or too slow, you don’t feel well.