|
|
Thyroid Diseases
On this page:
The thyroid is a small gland in the neck, just under the Adam's
apple. Shaped like a butterfly, the thyroid plays an important role in a person's
health and affects every organ, tissue, and cell in the body. It makes hormones
that help to regulate the body's metabolism (how the body uses and
stores energy from foods eaten) and organ functions. When the thyroid is not
working properly (called thyroid disorder), it can affect your body
weight, energy level, muscle strength, skin health, menstrual cycle (periods),
memory, heart rate, and cholesterol level. Thyroid disorders
happen: when the thyroid gland is not as active as it should be (called underactive
thyroid); when the thyroid is more active than it should be (called overactive
thyroid); or when the thyroid is enlarged (called goiter or
nodule). People with thyroid enlargement can have underactive, overactive
or normal thyroid function. Thyroid disorders are much more common in women
than in men. About 1 out of every 8 American women will develop a thyroid
disorder. Underactive or overactive thyroid can be found with a simple blood
test (called a thyroid stimulating hormone or TSH test),
and is most often treated with medication and sometimes surgery or radioactive
iodine.
Return to top 
Thyroid disorders include:
-
Hypothyroidism (underactive thyroid). This is the
most common type of thyroid disorder, where the thyroid makes too little
of the thyroid hormone that your body needs to function properly. It is
most often caused by Hashimoto's disease. With this disease,
the body's immune system (which normally protects you from
disease) thinks the thyroid is a foreign invader and tries to destroy
the thyroid. When damage is done to the thyroid, it can become larger
(called goiter). Not getting enough iodine in a person's
diet can also cause hypothyroidism, but this is more common outside of
the United States (in the U.S., many products such as salt and bread are
supplemented with iodine, making iodine deficiency rare).
Being female, over 40 years of age, having a close
family member with thyroid disease, and recently having had a baby are things
that can increase the chance of getting hypothyroidism.
-
Hyperthyroidism (overactive thyroid). When the thyroid
gland is overactive, it makes too much of the thyroid hormone that your body
needs to be healthy. This condition affects women more than men. In young
women, hyperthyroidism is most often caused by Graves' disease. With
this disease, the body's immune system tricks the thyroid into making too much
thyroid hormone. The entire thyroid becomes enlarged and overactive. Older
women may get another form of hyperthyroidism (toxic nodular goiter),
where overactive thyroid cells group together and form a lump in the neck
(called a thyroid nodule) that makes more of the thyroid hormone than
the body needs. Some thyroid disorders initially cause overactive thyroid, but
at a later point in time cause underactive thyroid, due to damage done to the
thyroid gland.
-
Postpartum thyroiditis. After giving birth, a woman's
thyroid can swell and become larger or inflamed. This can cause changing
levels of thyroid hormone in the body. Sometimes high levels can be followed
by low levels of thyroid hormone. After 6 months or less, this condition
usually goes away with no permanent damage to the thyroid. While common,
thyroid disorders after pregnancy are often hard to detect since some
of the symptoms, such as having trouble sleeping, fatigue,
depression, or weight change are viewed as normal when a
woman has a new baby. The symptoms can also be mild. Usually only short-term
treatment is required until the thyroid recovers normal function. Sometimes
after pregnancy, a woman can get hypothyroidism (underactive thyroid),
which persists and needs long-term treatment with medication.
-
Thyroid cancer. This type of cancer is most often
found as a lump (or nodule) in the thyroid gland. It is not a common type
of cancer and most thyroid nodules are benign (not cancer).
Other signs of thyroid cancer include swelling in the lymph nodes of the
neck and trouble swallowing or breathing. Although anyone can get thyroid
cancer, people who as children had head or neck x-ray treatments for tonsillitis
or other conditions (from about the 1920s to the 1960s) are more likely
to get this cancer. It is treated with surgery, which removes the cancer,
sometimes followed by radioactive iodine therapy, which kills
the cancer.
Return to top
It can be hard to tell if you have a thyroid disorder because these disorders
can have signs that are common and often confused with other conditions. If you
think you have a thyroid disorder, talk with your health care provider and ask
if a blood test for a thyroid disorder is indicated. A simple blood test
measures thyroid stimulating hormone, or TSH, to find overactive and
underactive thyroid disorders.
Signs of hypothyroidism, or underactive thyroid, include:
- Fatigue
- Weight gain
- Mood swings
- Forgetfulness
- Hoarse voice
- Dry, coarse skin and hair
- Trouble swallowing
- Not being able to stand the cold
- Increased cholesterol
- Heavy or irregular periods or trouble getting pregnant
- An enlarged thyroid (goiter)
Signs of hyperthyroidism, or overactive thyroid, include:
- Weight loss
- Feeling irritable and nervous
- Weakness in muscles and tremors
- Having menstrual periods that are not regular
- Troubled, or disturbed sleep
- Problems seeing or eye irritations
- Having an enlarged thyroid (goiter)
- Not being able to stand the heat
- Palpitations or rapid heart beats
- Frequent bowel movements
Return to top
Thyroid disease can be treated with medication alone or with surgery,
radioactive iodine or a combination of these treatments. Hypothyroidism
(underactive thyroid) is treated with thyroid replacement therapy. A synthetic
hormone is taken daily to increase the amount of thyroid hormone in a person's
body. The drug most health care providers prescribe is levothyroxine
sodium. This is the same hormone the thyroid normally makes. Treatment for
hyperthyroidism (overactive thyroid) aims to decrease the amount of thyroid
hormone in a person's body. This is done through medications that block the
formation and release of thyroid hormone into the body or with radioactive
iodine treatment, which destroys the overactive thyroid tissue. Surgery can
also be done to remove part or all of the thyroid gland, but this is usually
done to remove a nodule rather than to treat overactive thyroid. If you have
ever had a thyroid disorder, it is important to check your thyroid levels with
your health care provider on a regular basis.
Return to top
Office of Scientific
and Health Information
Thyroid Foundation of America,
Inc.
The American Thyroid Association
American Foundation
of Thyroid Patients
Endocrine Society
Return to top
|
Anorexia
