The thyroid is a small gland in the front of the neck that lies underneath the skin and muscles. It has two halves, referred to as lobes, that are reddish brown and resemble butterfly wings. A thyroid gland weighs less than 1 oz. and generates the hormones that regulate growth and control metabolism. The thyroid works in conjunction with the pituitary glands to control the flow of hormones.
How it Works
The thyroid gland works by absorbing iodine from food and water. Nearly one-third of the 50 mg. of iodine in the body is stored in the thyroid. Combined with the essential amino acid thyrosine, the thyroid manufactures hormones that are released into the body. Thyroid hormones control the growth of bones and sexual development and direct many organ functions.
Problems
Problems that can occur as a result of a malfunctioning thyroid gland include hypothyroidism and hyperthyroidism. Additionally, report doctors at the Mayo Clinic, nodules can develop in the thyroid that can turn into cancer. Thyroid nodules are fluid-filled lumps that also can grow to put pressure on the windpipe, making swallowing difficult. Hypothyroidism is a condition also referred to as under-active thyroid because it fails to produce a sufficient amount of hormones for proper metabolism. Hyperthyroidism has the opposite effect, causing an overactive thyroid that can lead to Graves' disease, characterized by bulging eyes.
Effects
An inadequate supply of thyroid hormones can cause the body to use up energy more quickly than it should or to store energy that turns to fat. An under-active thyroid can cause weight gain, fatigue and difficulty getting warm. It affects women more often than men. Too many thyroid hormones flowing through the body can cause weight loss, sensitivity to heat and a rapid heart rate.
Complications
Thyroid cancer typically is treated with surgery to remove the gland. Radioactive iodine treatment follows surgery to kill any remaining cancer cells. A replacement drug, called levothyroxine is prescribed to patients for the rest of their lives to perform the job of the thyroid. The drug ensures proper hormone function and suppresses the pituitary glands production of thyroid stimulating hormones.
Treatments
Thyroid hormone replacements are common treatments for hypothyroidism and hyperthyroidism. According to the American Thyroid Association, synthetic thyroxine (T4) closely replicates the body's production of the hormone. Dosage for the medication depends on the patient's weight, height and age, and the it usually requires periodic adjustment. Patients on T4 must be closely monitored to make sure the absorption rate is consistent with the dosage. Various medications, such as those for depression, can interfere with the effectiveness of thyroid medicines.
