People with fast metabolisms may have a lean build, small joints, long limbs, stringy muscles and seem unable to gain weight. Short, intense weight-lifting workouts that focus on big muscle groups and increasing the number of calories in your diet can help you gain weight if you have a fast metabolism. Hyperthyroidism is a thyroid disease that may accelerate your metabolism and prevent you from gaining weight.
If you have hyperthyroidism, you may experience sudden weight loss despite having a normal or increased appetite. Irregular heart beats and a faster-than-normal pulse may also occur. You may feel nervous, anxious or irritable. Sweating and a tremor in your fingers or hands may occur with this disease. Individuals with hyperthyroidism may have difficulty sleeping and may experience changes in bowel movement patterns and higher sensitivity to heat. Women may experience changes in their menstrual cycle. Hyperthyroidism typically enlarges your thyroid gland and may appear as swelling at the base of your neck. Older adults may not experience symptoms or only show subtle signs of the disease. Hyperthyroidism sometimes occurs with Graves' ophthalmopathy, a condition that causes you eyes to bulge out of their orbits.
Medical conditions and other diseases may cause your thyroid to release too much thyroid hormone over short or longer periods and lead to hyperthyroidism. Ingesting too much iodine in your diet may also lead to hyperthyroidism. Medline Plus suggests that Grave's Disease causes most cases of hyperthyroidism. Non-cancerous growths or tumors on your thyroid gland, testes or ovaries can also cause hyperthyroidism, as can overmedicating with synthetic thyroid hormone and inflammation of your thyroid gland.
Heart problems that are associated with hyperthyroidism include a rapid heart rate, arterial fibrillation and congestive heart failure. Excessive thyroid hormone prevents your body from supplying calcium and other minerals to your bones. Hyperthyroidism can weaken your bones and lead to osteoporosis. Graves' ophthalmopathy increases your sensitivity to light and may cause blurry or double vision. Your symptoms of hyperthyroidism may suddenly intensify and lead to a fever, rapid pulse and delirium.
Treatment for hyperthyroidism includes medication, iodine treatment and surgery. Anti-thyroid medications help suppress the activity of your thyroid to bring hormone secretions back down to normal. A radioactive iodine treatment destroy your thyroid gland to stop hormone overproduction. A physician may also recommend removing your thyroid surgically. You must take hormone replacement medication if you undergo iodine treatment or surgical removal of your thyroid. Beta-blocker medications treat symptoms of hyperthyroidism such as a rapid pulse, sweating and anxiety.