Question: What is (are) Hypothyroidism ?
Answer: The thyroid is a 2-inch-long, butterfly-shaped gland weighing less than 1 ounce. Located in the front of the neck below the larynx, or voice box, it has two lobes, one on each side of the windpipe. The thyroid is one of the glands that make up the endocrine system. The glands of the endocrine system produce and store hormones and release them into the bloodstream. The hormones then travel through the body and direct the activity of the bodys cells. The thyroid gland makes two thyroid hormones, triiodothyronine (T3) and thyroxine (T4). T3 is made from T4 and is the more active hormone, directly affecting the tissues. Thyroid hormones affect metabolism, brain development, breathing, heart and nervous system functions, body temperature, muscle strength, skin dryness, menstrual cycles, weight, and cholesterol levels.
Source: NIDDK

Question: What to do for Hypothyroidism ?
Answer: Experts recommend that people eat a balanced diet to obtain most nutrients. More information about diet and nutrition can be found on the National Agricultural Library website at www.nutrition.gov. Dietary Supplements Iodine is an essential mineral for the thyroid. However, people with autoimmune thyroid disease may be sensitive to harmful side effects from iodine. Taking iodine drops or eating foods containing large amounts of iodinesuch as seaweed, dulse, or kelpmay cause or worsen hypothyroidism or hyperthyroidism. More information about iodine can be found in the National Library of Medicine fact sheet Iodine in diet, available at www.nlm.nih.gov/medlineplus/ency/article/002421.htm. Women need more iodine when they are pregnantabout 250 micrograms a day because the baby gets iodine from the mothers diet. In the United States, about 7 percent of pregnant women may not get enough iodine in their diet or through prenatal vitamins.3 Choosing iodized salt salt supplemented with iodineover plain salt and prenatal vitamins containing iodine will ensure this need is met. To help ensure coordinated and safe care, people should discuss their use of dietary supplements, such as iodine, with their health care provider. Tips for talking with health care providers are available through the National Center for Complementary and Integrative Health.
Source: NIDDK