There are several basic disorders of the thyroid gland, which is located in the neck. The two most common problems of the thyroid are hypothyroidism and hyperthyroidism. Hypothyroidism is a condition in which the thyroid is under active and does not produce the appropriate level of hormones into one's body. Hyperthyroidism is the opposite problem, meaning too much hormone is produce and release. Other diseases can cause the immune system to attack the thyroid gland, usually producing hypothyroidism. Hurthle cell cancer is a rare form of cancer that affects the thyroid.
Hypothyroidism
When the thyroid gland is not as active as it should be, it can induce a variety of symptoms that affect the over all physical and mental aspects of the body. For example, it can make one feel sluggish and fatigued much of the time. It can cause joint problems, such as swelling, stiffness and pain. It can affect the muscles in a similar manner, causing stiffness, tenderness and aching. It also can make muscles feel weak. For women, hypothyroidism can induce menstrual bleeding that is heavier than usual. The disorder also can cause mental depression as well as increasing the cholesterol levels in the body and increasing body weight. The Mayo Clinic reports hypothyroid symptoms tend to get worse gradually if the condition is not treated.
Hyperthyroidism
Hyperthyroidism or an overactive thyroid gland can have many of the opposite effects of hypothyroidism. For example, with this condition there may be a sudden loss of weight without attempting to diet. This may occur even though one is eating the same amount of food as usual. Increasing the food one eats may not help the problem. The release of too much of the normal thyroid hormone also may speed up the heart faster than 100 beats each minute at rest. This condition is called tachycardia and may lead to high blood pressure and heart attacks. An irregular heartbeat or heart palpitations also are possible symptoms. The disorder also can affect one's mental state, causing such symptoms as irritability, anxiety and nervousness. Hyperthyroidism also can produce symptoms similar to hypothyroidism, such as weakness in the muscles and general fatigue. Grave's disease and Hashimoto's disease both may cause hyperthyroidism by forcing the immune system to attack the thyroid gland.
Thyroid Cancer
The Mayo Clinic states that cancer of the thyroid gland, such as Hurthle cell cancer, is not common, especially in the United States. Thyroid cancer typically does not produce symptoms in the early part of the disease's growth. In Hurthle cell cancer, however, early symptoms may include a lump that grows quickly in the neck. This is the most easily recognizable sign of the disease. Other symptoms include difficulty swallowing, neck or throat pain, vocal changes, breathing problems such as being short of breath and a cough that is continual.
