Hypothyroidism -- an underactive thyroid -- is second only to diabetes as the most common endocrine disorder in the United States. Although hypothyroidism becomes more common as you grow older, it can occur at any age as a result of inflammatory thyroid diseases, such as Hashimoto's thyroiditis, or from loss of normal pituitary stimulation of your thyroid gland. Although iodine is required for thyroid hormone production, mineral supplements are generally of little value in controlling an underactive thyroid.
Thyroid Hormones
Your thyroid gland is located in the front of your neck, just below your "Adam's apple." Its sole purpose is to produce iodine-containing thyroid hormones -- triiodothyronine, or T3, and thyroxine, or T4 -- which control the metabolic activities of virtually every cell in your body. Your thyroid has developed the unique ability to capture iodine from your bloodstream, combine it with the amino acid tyrosine, and combine iodotyrosine molecules to synthesize T3 and T4, which are then released into your bloodstream.
Goiter
Iodine is an essential mineral for normal thyroid function. According to the University of Connecticut Health Center, you need to consume at least 150 mcg of iodine daily to produce sufficient amounts of T3 and T4. An intake of less than 50 mcg daily is associated with a condition called goiter, which involves a painless swelling of your thyroid as it enlarges to trap more iodine from your bloodstream. However, too much iodine -- 1,100 mcg daily is the tolerable upper limit -- actually inhibits the production and secretion of T3 and T4.
Treatment
If your thyroid is functioning below its normal level, the only time a mineral supplement will be helpful is when you have an iodine-deficient goiter, and iodine is the only mineral that is necessary or useful for this condition. Otherwise, hypothyroidism is treated with thyroid hormone replacement. Insufficient levels of T3 and T4 can lead to weight gain, menstrual problems, cold intolerance, fatigue, weakness, hair loss, constipation, skin thickening, poor mental function and heart failure.
Considerations
Hypothyroidism is relatively common, particularly among the elderly and in persons who have inflammatory thyroid diseases. Iodine is singularly important for the production of thyroid hormones, and iodine supplementation is necessary if you have goiter caused by iodine deficiency. However, supplementation with other minerals will not correct the symptoms caused by hypothyroidism. If you think your thyroid is underactive, see your doctor to have it checked. A simple panel of blood tests will determine if you need thyroid hormone therapy.
