Your thyroid, a small butterfly-shaped gland in the front of your neck under your Adam’s apple, controls more than you realize when it comes to your health. It regulates your metabolism, which is how your body turns food into energy, and it also affects your heart, muscles, bones, and cholesterol.
It controls how fast you burn calories, and it can affect the speed of your heartbeat, your body temperature, how fast you digest food, and how your muscles contract.
Two conditions—an overactive thyroid gland (hyperthyroidism) and an underactive thyroid gland (hypothyroidism) happen if your thyroid isn’t working properly.
How does your thyroid work?
The thyroid gland uses iodine from food to make two hormones: triiodothyronine(T3) and thyroxine(T4). The pituitary gland, which is in the brain, helps control the thyroid gland. It releases thyroid-stimulating hormone (TSH). The release of TSH into the bloodstream makes the thyroid gland release thyroid hormones. When the pituitary gland detects that thyroid hormone levels are too low, it releases more TSH. If the pituitary gland detects too much thyroid hormone, it releases less TSH.
Hyperthyroidism
An overactive thyroid gland generates too much thyroid hormone, which speeds up metabolism. Common symptoms of hyperthyroidism include:
- Rapid heart rate
- Frequent bowel movements, even diarrhea
- Excessive perspiration
- Weakness
- Insomnia
- Irritability and anxiety
- Increased appetite
- Weight loss
The first line of treatment for an overactive thyroid gland is drug therapy. If that doesn’t resolve the problem, a dose of radioactive iodine may fix the problem by destroying thyroid cells. Sometimes the treatment damages so much of the gland that it can’t produce enough thyroid hormone and it becomes necessary to take thyroid hormone. Surgery to remove some of the thyroid gland can be an option when other treatments don’t work or aren’t advisable.
Hypothroidism
An underactive thyroid gland doesn’t generate enough thyroid hormone. This condition, which slows metabolism, is increasingly common with age. It can also be caused by Hashimoto’s disease, a condition in which the body’s immune system attacks the thyroid gland, or by thyroiditis, an inflammation of the gland.
Symptoms of hypothyroidism include:
- Feeling tired, weak, or depressed
- Dry skin and brittle nails
- Sensitivity to the cold
- Memory problems or trouble thinking clearly
- Constipation
- Muscle pain
- Hair loss
- Weight gain
Hypothyroidism is usually treated by taking thyroid hormone.
Risk factors
Although anyone can develop hypothyroidism, you’re at an increased risk if you:
- Are a woman
- Are older than 60
- Have a family history of thyroid disease
- Have an autoimmune disease, such as type 1 diabetes or celiac disease
- Have been treated with radioactive iodine or anti-thyroid medications
- Received radiation to your neck or upper chest
- Have had thyroid surgery (partial thyroidectomy)
Complications
Untreated hypothyroidism can lead to goiters, heart problems, mental health issues, peripheral neuropathy (nerve damage in your arms and legs for example), Myxedema (a rare, life-threatening condition, the result of long-term, undiagnosed hypothyroidism) and more.
If your thyroid problem is mild, you may have no symptoms and your doctor may discover it while running tests for another reason.
Sources: Healthwise,Inc., Harvard Health, Mayo Clinic
