How Thyroid Affects Everything

The thyroid gland is one of the most important organs in the body, responsible for producing hormones that help control metabolism and other bodily functions. Several conditions may develop if the thyroid has too much or too little of these hormones that can directly affect different processes throughout your body, including brain development, menstrual cycles and nervous system function.

What Is the Thyroid Gland?

The thyroid gland is a butterfly-shaped organ located in the lower front of the neck, just above the collarbone. It is one of the body's endocrine glands, which makes hormones secreted into every tissue in the body through the blood. Thyroid hormones play a crucial role in regulating your weight, body temperature, muscle strength and even your mood.

Thyroid disease is a general term that refers to abnormalities or changes in thyroid hormone production. Some of the most common thyroid conditions include:

Goiter - enlargement of the thyroid gland
Hyperthyroidism - overproduction of thyroid hormones
Hypothyroidism - underproduction of thyroid hormones
Thyroid nodules - lumps in the thyroid gland
Thyroiditis - swelling of the thyroid
Thyroid cancer

Common symptoms of thyroid disease may include some of the following:

Goiter	Hypothyroid	Hyperthyroid	Thyroid Nodules	Thyroiditis	Thyroid Cancer
Swelling in the neck	Feeling cold when other people do not	Weight loss	MAY have a bump either side of windpipe	Not obvious – may be detected via blood test	Nodule
Not always obvious	Constipation	Eating more	Not always obvious		Hoarse voice
	Muscle weakness	Rapid or irregular heartbeat			Not always obvious
	Weight gain, even though you are not eating more food	Nervous or anxious
	Joint or muscle pain	Irritable
	Feeling sad or depressed	Trouble sleeping
	Fatigue	Trembling in your hands and fingers
	Pale, dry skin	Increased sweating
	Dry, thinning hair	Feeling hot when other people do not
	Slow heart rate	Muscle weakness
	Less sweating than usual	Diarrhea or more bowel movements than normal
	Puffy face	Fewer and lighter menstrual periods than normal
	Hoarse voice	Changes in your eyes that can include bulging, redness or irritation
	Heavier menstrual bleeding

Goiter

Swelling in the neck
Not always obvious

Hypothyroid

Feeling cold when other people do not
Constipation
Muscle weakness
Weight gain, even though you are not eating more food
Joint or muscle pain
Feeling sad or depressed
Fatigue
Pale, dry skin
Dry, thinning hair
Slow heart rate
Less sweating than usual
Puffy face
Hoarse voice
Heavier menstrual bleeding

Hyperthyroid

Weight loss
Eating more
Rapid or irregular heartbeat
Nervous or anxious
Irritable
Trouble sleeping
Trembling in your hands and fingers
Increased sweating
Feeling hot when other people do not
Muscle weakness
Diarrhea or more bowel movements than normal
Fewer and lighter menstrual periods than normal
Changes in your eyes that can include bulging, redness or irritation

Thyroid Nodules

MAY have a bump either side of windpipe
Not always obvious

Thyroiditis

Not obvious – may be detected via blood test

Thyroid Cancer

Nodule
Hoarse voice
Not always obvious

Your doctor may ask you about your medical history and conduct a physical examination, thyroid tests and imaging tests to help diagnose thyroid diseases. Thyroid tests include the following:

Blood tests

TSH tests - changes in the TSH level in the blood can serve as an early warning system when thyroid hormones in the body become too high or too low. An elevated TSH means the thyroid gland is not making enough thyroid hormone, while a low TSH level indicates that the thyroid is producing too much thyroid hormone
T4 tests - measuring free T4 (FT4) and TSH levels more accurately reflect how the thyroid gland functions. T4 is the main form of thyroid hormone circulating in the blood
T3 tests – diagnostic test to determine the severity of hyperthyroidism. However, T3 testing is rarely helpful in checking for hypothyroidism since it is the last test to become abnormal. A person can have severe hypothyroidism with a high TSH and low FT4 or free T4 index (FTI) but have normal T3

Thyroid antibody tests

Help diagnose the cause of thyroid problems by measuring the levels of thyroid antibodies, such as lymphocytes in the blood

Nonblood tests

Radioactive iodine uptake - measures how the thyroid gland takes up much radioactive iodine in a particular time to determine whether the gland is functioning correctly and find the cause of hyperthyroidism

Though you may not prevent thyroid disease, getting treatment early on can help prevent its complications. Treatment may include biopsy, medicine, radioiodine therapy or thyroid surgery. If you think you have a thyroid disorder, consult with an endocrinologist right away. Please do not delay care.

Sources:
American Thyroid Association
MedlinePlus
U.S. Health and Human Services, Office of Women’s Health