Through the hormones it produces, the thyroid gland influences almost all of the metabolic processes in your body. Thyroid disorders can range from a small, harmlessgoiter (enlarged gland) that needs no treatment to life-threatening cancer. The most common thyroid problemsinvolve abnormal production of thyroid hormones. Too much thyroid hormone results in a condition known as hyperthyroidism. Insufficient hormone production leads tohypothyroidism.
What Causes Thyroid Problems?
All types of hyperthyroidism are due to an overproduction of thyroid hormones, but the condition can occur in several ways:
- Graves’ disease: The production of too much thyroid hormone.
- Toxic adenomas: Nodules develop in the thyroid gland and begin to secrete thyroid hormones, upsetting the body’s chemical balance; some goiters may contain several of these nodules.
- Subacute thyroiditis: Inflammation of the thyroid that causes the gland to “leak” excess hormones, resulting in temporary hyperthyroidism that generally lasts a few weeks but may persist for months.
- Pituitary gland malfunctions or cancerous growths in the thyroid gland: Although rare, hyperthyroidism can also develop from these causes.
Hypothyroidism, by contrast, stems from an underproduction of thyroid hormones. Since your body’s energy production requires certain amounts of thyroid hormones, a drop in hormone production leads to lower energy levels. Causes of hypothyroidism include:
- Hashimoto’s thyroiditis: In this autoimmune disorder, the body attacks thyroid tissue. The tissue eventually dies and stops producing hormones.
- Removal of the thyroid gland: The thyroid may have been surgically removed or chemically destroyed.
- Exposure to excessive amounts of iodide: Cold and sinusmedicines, the heart medicine amiodarone, or certain contrast dyes given before some X-rays may expose you to too much iodine.You may be at greater risk for developing hypothyroidism if you have had thyroid problems in the past.
- Lithium: This drug has also been implicated as a cause of hypothyroidism.
Untreated for long periods of time, hypothyroidism can bring on a myxedema coma, a rare but potentially fatal condition that requires immediate hormone treatment.