Maybe you've been feeling sluggish lately and unable to concentrate. Or you're having heart palpitations and constantly feeling too warm. It might be time to have your thyroid checked. A small, butterfly-shaped gland located in front of your trachea and below your larynx, your thyroid produces hormones that control your metabolism. But sometimes this gland produces too much or too little hormone, causing an array of symptoms that bear looking into. Below are the most common thyroid problems, which collectively affect millions of Americans:

  • Hypothyroidism. According to the New York Thyroid Center, one in 10 women will show signs of a faltering thyroid by the age of 50. By age 60, 17 percent will have a slow thyroid. What are some indications that your thyroid is too slow? Common symptoms include fatigue, weight gain, dry skin, feeling cold, goiter (a lump in the neck), depression, lack of libido, hair loss, and menstrual difficulties or miscarriage. With hypothyroidism, your body consumes less oxygen and produces less heat. Basically, all of your physical and mental functions are operating at low speed. The treatment usually involves taking thyroid replacement hormones that mimic normal thyroid function.
  • Hyperthyroidism. The opposite of hypothyroidism, hyperthyroidism occurs when the body produces too much thyroid hormone. Typical symptoms include heart palpitations, feeling hot all the time, weight loss, fatigue, nervousness, and trembling. About 1 percent of women suffer from hyperthyroidism. The treatment may include antithyroid drugs, which prevent the thyroid from emitting hormones, or a single dose of radioactive iodine, administered orally, which kills off extra thyroid cells.
  • Thyroid nodules. These are small growths, either of thyroid tissue or fluid-filled cysts, that appear on the thyroid. Estimates are that up to half of all people will have them at some point, but they usually aren't noticeable until they grow to a half-inch across. About one out of 20 people will have nodules of this size, which can produce too much thyroid hormone or interfere with breathing or swallowing. Thyroid nodules may need to be surgically removed, or a physician may attempt to shrink them using thyroid-suppression hormones.