|
Iodine is an element (atomic number 53), which is required by humans for the synthesis of thyroid hormones (triiodothyronine/T3 and thyroxine/T4). Chronic iodine deficiency can lead to numerous health problems in children and adults, including thyroid gland dysfunction (including goiter) and various neurologic, gastrointestinal, and skin abnormalities. Iodine deficiency in pregnant or nursing mothers can lead to significant neurocognitive deficits in their infants. "Cretinism" or severe mental retardation is a rare outcome of severe iodine deficiency during early development. Growth stunting, apathy, impaired movement, or speech/hearing problems may occur. Many individuals living in developing countries may be at risk of iodine deficiency and its complications, and iodine deficiency is considered to be a preventable cause of mental retardation. Iodine deficiency is rare in industrialized countries such as the United States, due to enrichment of table salt and cattle feed with iodine. But deficiency is common in developing countries, where supplementation may be considered. Humans obtain iodine from their diets. The amount of iodine in food or water depends upon the amount of iodine in the local soil. Areas with mountainous (glacier) water or heavy rainfall tend to be low in iodine content, increasing the risk of iodine deficiency. This review does not discuss medical uses of radioactive iodine or iodine contrast agents used for imaging studies such as computerized tomography (CT scanning).
|
|
Nonmetallic element; a topical anti-infective agent.
|
|
Iodine is a trace mineral and an essential nutrient found naturally in the body.
|
|
Iodine is a trace mineral required for human life. Humans require iodine for proper physical and mental development.
|
|
Iodine is a critically important component of thyroid hormones. There are four iodine atoms per molecule of l-thyroxine, and three per molecule of l-triiodothyronine.
|
|
Antithyroid agent, antisporotrichotic agent, and expectorant.
|
|
Selenium is a trace mineral found in soil, water, and some foods. It is an essential element in several metabolic pathways. Selenium deficiency can occur in areas where soil content of selenium is low, and may affect thyroid function and cause conditions such as Keshan disease. Selenium deficiency is also commonly seen in patients on total parenteral nutrition (TPN) as their sole source of nutrition. Gastrointestinal disorders may decrease the absorption of selenium resulting in depletion or deficiency. Selenium may be destroyed when foods are refined or processed. Specific dietary sources of selenium include brewer's yeast, wheat germ, butter, garlic, grains, sunflower seeds, Brazil nuts, walnuts, raisins, liver, kidney, shellfish (lobster, oyster, shrimp, scallops), fresh-water and salt-water fish (red snapper, salmon, swordfish, tuna, mackerel, halibut, flounder, herring, smelts). Selenium is also found in alfalfa, burdock root, catnip, fennel seed, ginseng, raspberry leaf, radish, horseradish, onion, chives, medicinal mushrooms (reishi, shiitake), and yarrow. The role of selenium in cancer prevention has been the subject of recent study and debate. Initial evidence from the Nutritional Prevention of Cancer (NPC) trial suggests that selenium supplementation reduces the risk of prostate cancer among men with normal baseline PSA (prostate specific antigen) levels, and low selenium blood levels. However, in this study selenium did not reduce the risk of lung, colorectal, or basal cell carcinoma of the skin, and actually increased the risk of squamous cell skin carcinoma. The ongoing Selenium and Vitamin E Cancer Prevention Trial (SELECT) aims to definitively address the role of selenium in prostate cancer prevention.
|
![]() |
Selenium is an essential trace mineral. Small amounts of selenium are good for your health.
|
|
|
Selenium is a nonmetallic element with an atomic number of 34 and an atomic weight of 78.96.
|