The thyroid is a gland located in the neck that is responsible for secreting hormones that control the body's metabolism. These hormones are known as T3 and T4 and help regulate energy use, according to the Cleveland Clinic. Too much or too little of these hormones can result in either excess energy or not enough energy.
Types
The signs of thyroid imbalance depend on the amount of hormone being produced. Too little thyroid hormone is known as hypothyroidism. Signs of hypothyroidism include fatigue, weight gain, dry skin, voice changes, cold intolerance and in some cases, memory problems and heavy menstrual periods. Excess thyroid hormone is known as hyperthyroidism. Common signs of this imbalance include anxiety, muscle weakness, weight loss, heat intolerance and light menstrual periods.
Causes
The signs of thyroid imbalance are caused by diseases that result in either hypo- or hyperthyroidism. Common causes of hypothyroidism include inflammation of the thyroid gland, deficiency of the mineral iodine or an autoimmune thyroid issue. Iodine is used by the thyroid to help produce thyroid hormone. While deficiency is uncommon in the United States, it can be a problem in other areas of the world. Inflammation of the thyroid gland can occur after pregnancy and can cause first hyperthyroidism and then hypothyroidism, resulting in a range of symptoms. Causes of hyperthyroidism include an enlarged, overactive thyroid gland, thyroid inflammation or excessive iodine.
Diagnosis
If signs of a thyroid imbalance are apparent, testing can be performed to diagnose the thyroid disorder. The first test is typically a blood test looking at the level of thyroid hormone and of thyroid stimulating hormone in the bloodstream. This can detect whether too much or too little thyroid hormone is being produced and can also help determine whether the problem is with the thyroid gland itself. If too much thyroid hormone is found, further testing using an ultrasound can determine why the thyroid gland is overactive.
Treatment
For hypothyroidism, treatment with synthetic thyroid hormone is typically initiated. Levels are monitored to ensure that treatment is adequate. With treatment, the signs of hypothyroidism should be ameliorated. For hyperthyroidism, the therapy depends on the cause of the disorder. Radioactive iodine can be used to shrink the thyroid gland and slow down thyroid activity. Anti-thyroid medications are also used to stop the thyroid gland from producing too much thyroid hormone.
Complications
With treatment, the signs of thyroid imbalance typically resolve. High or low levels of thyroid hormone can lead to drastic weight changes, heart problems and fertility issues. Hypothyroidism can result in damage to the nerves over time and can lead to birth defects in pregnant women. Patients with too much thyroid hormone can have osteoporosis, or weakened bones. Patients can also have skin issues and eye problems if they are not treated.
