Iodine, a trace mineral, is required by the body for the synthesis of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3). Under normal circumstances, your body contains approximately 20 to 30 mg of iodine, most of which is stored in your thyroid gland. Smaller amounts of iodine are also found in lactating mammary glands, the stomach lining, salivary glands, and in the blood. Without sufficient iodine, your body is unable to synthesize these hormones, and because the thyroid hormones regulate metabolism in every cell of the body and play a role in virtually all physiological functions, an iodine deficiency can have a devastating impact on your health and well-being.
In areas where there is little iodine in the diet, iodine deficiency gives rise to hypothyroidism, symptoms of which are extreme fatigue, goitre, mental slowing, depression, weight gain, and low basal body temperatures. Iodine deficiency is the leading cause of preventable mental retardation, a result which occurs primarily when babies or small children are rendered hypothyroidic by a lack of the element. Concentrated food sources of iodine include sea vegetables, yogurt, cow's milk, eggs, strawberries and mozzarella cheese. Fish and shellfish can also be concentrated sources of iodine.
