The thyroid is a small gland that helps regulate a person’s metabolism by producing hormones.
Problems can occur if the thyroid overproduces hormones, when it is known as hyperthyroidism, or under produced hormones, which is called hypothyroidism. These issues may also result in the growth of the thyroid, which is called a goiter.
In hyperthyroidism, the thyroid gland is overactive. It produces too much of its hormone. Hyperthyroidism affects about 1 percent of women. It’s less common in men.
Excessive thyroid hormone production leads to symptoms such as:
- racing heart
- increased sweating
- trouble sleeping
- thin skin
- brittle hair and nails
- muscle weakness
- weight loss
- bulging eyes (in Graves’ disease)
Hypothyroidism is the opposite of hyperthyroidism. The thyroid gland is underactive, and it can’t produce enough of its hormones.
Hypothyroidism is often caused by Hashimoto’s disease, surgery to remove the thyroid gland, or damage from radiation treatment.
Too little thyroid hormone production leads to symptoms such as:
- dry skin
- increased sensitivity to cold
- memory problems
- weight gain
- slow heart rate
Thyroid nodules are lumps on a person’s thyroid. They can appear alone or in groups and are very common.
It is not clear why people develop thyroid nodules. Thyroid nodules do not typically cause symptoms, although there is a chance they may cause hyperthyroidism by becoming overactive.
A doctor will be able to feel thyroid nodules on a person’s neck, during an examination. If they discover nodules, they may check for hyperthyroidism or hypothyroidism.