A Look at Thyroid Disorders
The thyroid gland, located in the front of the neck just below the Adam’s apple, takes iodine from the diet and makes thyroid hormone. Thyroid hormone affects a person’s physical energy, temperature, weight and mood.
Thyroid diseases generally fall into two broad groups of disorders: abnormal function and abnormal growth (nodules) in the gland. These problems are common in the general population, especially among older people and women. Most thyroid problems can be detected and treated.
Functional disorders are usually related to the gland producing too little thyroid hormone (hypothyroidism) or too much thyroid hormone (hyperthyroidism).
Benign nodules in the thyroid gland are common and do not usually cause serious health problems. These nodules occur when the cell growth within the nodule is abnormal. Nodules can occasionally put pressure on the neck and cause trouble with swallowing, breathing or speaking if they are too large. The thyroid usually functions normally even when nodules are present.
Thyroid cancers are much less common than benign nodules. With treatment, the cure rate for thyroid cancer is more than 90 percent.
The two most common forms of thyroid disorder are hyperthyroidism and hypothyroidism.
What is hypothyroidism?
Hypothyroidism (hahy-puh-thahy-roi-diz-uh m) is when your thyroid does not make enough thyroid hormones. It is also called underactive thyroid. The most common cause of hypothyroidism in the United States is Hashimoto’s thyroiditis. Hashimoto’s thyroiditis is an autoimmune disease, in which the immune system mistakenly attacks the thyroid. This attack damages the thyroid so that it does not make enough hormones. Hypothyroidism also can be caused by:
- Treatment of hyperthyroidism
- Radiation treatment of certain cancers
- Thyroid removal
In rare cases, problems with the pituitary gland can cause the thyroid to be less active.
What are the symptoms of hypothyroidism?
Symptoms of hypothyroidism tend to develop slowly, often over several years. At first, you may just feel tired and sluggish. Later, you may develop other symptoms of a slowed down metabolism, including:
- Weight gain, even though you are not eating more food
- Increased sensitivity to cold
- Muscle weakness
- Joint or muscle pain
- Fatigue (feeling very tired)
- Pale dry skin
- A puffy face
- A hoarse voice
- Excessive menstrual bleeding
In addition to these symptoms, people with hypothyroidism may have high blood levels of LDL cholesterol. This is the so-called “bad” cholesterol, which can increase your risk for heart disease.
What is hyperthyroidism?
Some disorders cause the thyroid to make more thyroid hormones than the body needs. This is called hyperthyroidism (hahy-per-thahy-roi-diz-uhm), or overactive thyroid. The most common cause of hyperthyroidism is Graves’ disease. Graves’ disease is an autoimmune disorder, in which the body’s own defense system, called the immune system, stimulates the thyroid. This causes it to make too much of the thyroid hormones.
What are the symptoms of hyperthyroidism?
At first, you might not notice symptoms of hyperthyroidism. They usually begin slowly. But over time, a speeded up metabolism can cause symptoms such as:
- Weight loss, even if you eat the same or more food
- Eating more than usual
- Rapid or irregular heartbeat or pounding of your heart
- Trouble sleeping
- Trembling in your hands and fingers
- Increased sweating
- Increased sensitivity to heat
- Muscle weakness
- More frequent bowel movements
- Less frequent menstrual periods with lighter than normal menstrual flow
In addition to these symptoms, people with hyperthyroidism may have osteoporosis, or weak, brittle bones. In fact, hyperthyroidism might affect your bones before you have any of the other symptoms of the disorder. This is especially true of postmenopausal women, who are already at high risk of osteoporosis.
Medical information within this site is not intended for use in the diagnosis or treatment of any health condition. Please consult a licensed health care professional for the treatment or diagnosis of any medical condition.