Hyperthyroidism occurs when your thyroid gland is overproducing thyroid hormones. This can cause symptoms that may include weight loss and increased appetite.
Several health conditions can lead to hyperthyroidism, most commonly Graves’ disease.
The thyroid is a small, butterfly-shaped gland located at the front of your neck. It produces thyroxine (T4) and triiodothyronine (T3), which are two primary hormones that control how your cells use energy. Your thyroid gland regulates your metabolism through the release of these hormones.
When your thyroid makes too much T3, T4, or both, it speeds upTrusted Source your body’s systems, causing distress. Timely diagnosis and treatment of hyperthyroidism can relieve symptoms and prevent complications.
What causes hyperthyroidism?
A variety of conditions can cause hyperthyroidism. Graves’ disease, an autoimmune disorder, is the most common cause of hyperthyroidism. In Graves’ disease, your immune system attacks your thyroid with antibodies, resulting in the release of too much hormone.
Graves’ disease occurs more often in women than in men. A 2011 research Source explains that genetics largely determine whether someone will develop Graves’, although environmental factors also play a role. Studies of families and twins indicate Graves’ disease isn’t caused by a single gene defect, but rather by small changes in multiple genes.
Tell your doctor if any relatives have been diagnosed with hyperthyroidism, so they can get an accurate picture of your risk factors.
Aside from Graves’ disease, other of hyperthyroidism include:
Excess iodine. This mineral is a key ingredient in T4 and T3, and too much can cause temporary hyperthyroidism. Iodine can be ingested through food like fish and dairy. It is also present in certain medications, such as amiodarone (for heart arrhythmia), cough syrups, and medical contrast dyes.
Thyroiditis (inflammation of the thyroid). Thyroiditis refers to conditions which cause the thyroid gland to swell, making either too much or too little of the hormone.
Benign thyroid nodules. Nodules are lumps that develop on the thyroid gland, often for unknown reasons. Some thyroid nodules produce excess thyroid hormones, but the majority are benign. Nodules are also called benign tumors or adenoma.
Toxic thyroid nodules (toxic adenoma). Some thyroid nodules are malignant, or cancerous. Whether a nodule is benign or malignant is determined by , or with a kind of tissue biopsy called fine needle aspiration.
Tumors of the ovaries or testes.
Large amounts of T4 in the blood. High levels of T4 can result from taking certain dietary supplements, or too much of the thyroid hormone medication, levothyroxine
Vs. Thyrotoxicosis
Thyrotoxicosis and hyperthyroidism don’t mean the same thing, even though they’re sometimes used interchangeably. Hyperthyroidism (and its many forms) are actually all under the umbrella of thyrotoxicosis.
Hyperthyroidism refers to your thyroid’s physical overproduction of hormones. Thyrotoxicosis refers more broadly to the presence of too much thyroid in your body, regardless of whether it came from the gland, medication, or other cause.
What are the symptoms of hyperthyroidism?
Some symptoms of hyperthyroidism may be physically obvious, while others are subtle, and may be hard to notice at first. Sometimes hyperthyroidism is mistaken for anxiety.
According to the National Institutes of Health (NIH)Trusted Source, hallmark signs and symptoms of hyperthyroidism include:
weight loss, but with an increased appetite
rapid or irregular heartbeat
feeling nervous or irritable
feeling fatigued, but having trouble sleeping
hand tremors, muscle weakness
getting easily overheated
frequent bowel movements
The thyroid gland itself can swell into a goiter, which can be either symmetrical or one-sided. A goiter is an enlargement of the gland, and it’s often visible as a bulge or puffiness at the base of your neck. The most common causeTrusted Source of a goiter is iodine deficiency.
You may also experience prominent or bulging eyes. This is medically known as exophthalmos, and it’s associated with Graves’ disease.
Longterm and untreated thyroid disease can also cause brittle hair, and hair loss.
Complications
Untreated, hyperthyroidism can contribute to an increased risk of:
Thyroid storm. A thyroid storm is a rare health condition that occurs as a result of untreated hyperthyroidism. Your body enters overdrive as a result of too many thyroid hormones in its system. A thyroid storm is a potentially life threatening combination of symptoms including rapid heart rate, high blood pressure, and fever.
Pregnancy complications. This includes people with existing thyroid disorders and people who develop hyperthyroidism during pregnancy. High thyroid hormone levels can harm both pregnant people and the fetus. Risks include miscarriage and premature . Regular thyroid hormone tests during pregnancy can detect irregularities, and your doctor may determine medication is a good idea.
Osteoporosis. Hyperthyroidism can cause your bones to become weak and thin, which can lead to osteoporosis. Taking vitamin D and calcium supplements during and after treatment can help improve bone health. Getting adequate exercise or daily physical also helps prevent osteoporosis.
Cancer. Some people with hyperthyroidism develop thyroid cancer, called thyroid carcinoma. A 2018 overview reported that thyroid cancer in hyperthyroid patients was more “aggressive” and had a worse prognosis than in euthyroid patients (those with a healthy thyroid
