Your heart and brain get all the attention, but the real hero of your body is the butterfly-shaped gland beneath your voice. It produces two main hormones, triiodothyronine (T3) and thyroxine (T4), which enter the bloodstream and affect physiological functions from head to toe. “Every cell in your body needs thyroid hormone to function properly,” says J. Woody Sistronic, MD, board member of the American Thyroid Association. “They regulate everything from metabolism to bone health. A lot depends on whether your thyroid is healthy.”
If not, there is a problem. For example, if your thyroid is underactive, a condition called hypothyroidism can cause very low levels of T3 and T4; Hormones affect the nervous system, which can lead to forgetfulness or depression. If your thyroid is overactive, Dr. Sisteron explains, a condition called hyperthyroidism, a condition called excess T3 and T4 can make you feel irritable and anxious. An overactive thyroid can speed up your metabolism and cause weight loss. can lead to weight gain.
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Hypothyroidism can trigger menstruation and explain the dysfunction of the thyroid gland. Your Thyroid Affects Your Constipation #2: Hypothyroidism is associated with constipation, and an overactive thyroid can lead to frequent loose stools.
There is also a risk of developing serious health problems. Too much thyroid hormone causes the body to break down old bone faster than it can replace it, which accelerates osteoporosis. An overactive thyroid can cause atrial fibrillation and an irregular heart rhythm. On the other hand, hypothyroidism makes you prone to high cholesterol and blood pressure complications.
The most significant sign that your thyroid isn’t working properly is “feeling depressed,” says Risha Abednoola, M.D., an endocrinologist at the Cleveland Clinic. “You’re so tired you can’t do your daily routine or exercise regularly.” Fatigue doesn’t go away after a good night’s rest. This type of extreme fatigue is a symptom of both hypothyroidism and hyperthyroidism.
Being a woman increases your chances of developing thyroid disease and this is still a mystery. “Estrogen plays a role,” says Terry Davis, MD, director of the Mount Sinai Thyroid Center in New York. “Thyroid cells have many estrogen receptors,” he explains, which makes them particularly sensitive to female hormones.
There is evidence that many thyroid diseases are autoimmune disorders. For example, the most common cause of hypothyroidism is Hashimoto’s disease, while the most common cause of hyperthyroidism is Graves’ disease. They are also more likely to affect women. Your genes may also play a role: A 2017 study published in Clinical Thyroidology for the Public found that nearly half of Hashimoto’s patients have a family history.
The good news is that most thyroid disorders are treatable once diagnosed. Your doctor can find out what’s going on with scans and blood tests that measure levels of TSH, or thyroid-stimulating hormone. The pituitary gland secretes this hormone and stimulates the thyroid gland to produce T3 and T4.
In people with hypothyroidism, the thyroid gland does not respond well to TSH, and the pituitary gland overproduces the hormone to stimulate the release of T3 and T4. Conversely, when the thyroid is overactive, your brain senses that T3 and T4 levels are too high, and the pituitary gland does not produce TSH.
If you are diagnosed with hypothyroidism, your doctor will prescribe a synthetic form of thyroid hormone called levothyroxine. Dr. Sistronic says the once-a-day drug is very safe and should have few or no side effects when taken at the right dose.
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Hyperthyroidism is usually treated first with methimazole, which stops the thyroid gland from producing too much hormone, says Dr. Systonic.