<p>Your thyroid is a small, butterfly-shaped gland in the front of your neck. It makes <a href="https://medlineplus.gov/hormones.html">hormones</a> that control the way the body uses energy. These hormones affect nearly every organ in your body and control many of your body's most important functions. For example, they affect your breathing, heart rate, weight, digestion, and moods.</p> <p>Thyroid diseases cause your thyroid to make either too much or too little of the hormones. Some of the different thyroid diseases include:</p> <ul> <li>Goiter, an enlargement of the thyroid gland</li> <li><a href="https://medlineplus.gov/hyperthyroidism.html">Hyperthyroidism</a>, which happens when your thyroid gland makes more thyroid hormones than your body needs</li> <li><a href="https://medlineplus.gov/hypothyroidism.html">Hypothyroidism</a>, which happens when your thyroid gland does not make enough thyroid hormones</li> <li><a href="https://medlineplus.gov/thyroidcancer.html">Thyroid cancer</a></li> <li>Thyroid nodules, lumps in the thyroid gland</li> <li>Thyroiditis, swelling of the thyroid</li> </ul> <p>To diagnose thyroid diseases, your health care provider may use a medical history, physical exam, and <a href="https://medlineplus.gov/thyroidtests.html">thyroid tests</a>. In some cases, your provider may also do a <a href="https://medlineplus.gov/biopsy.html">biopsy</a>.</p> <p>Treatment depends on the problem, how severe it is, and what your symptoms are. Possible treatments may include medicines, radioiodine therapy, or thyroid surgery.</p> <p class="">Dept. of Health and Human Services Office on Women's Health</p>