In nutrition, Iodine is a trace mineral and an essential nutrient found naturally in the body. Iodine is needed for the normal metabolism of cells. Metabolism is the process of converting food into energy. Humans need iodine for normal thyroid function, and for the production of thyroid hormones.
Potassium iodide tablets, is also used to prevent the body from absorbing harmful radiation.
 Food Sources
Iodized salt -- table salt with iodine added -- is the main food source of iodine. Seafood is naturally rich in iodine. Cod, sea bass, haddock, and perch are good sources. Kelp is the most common vegetable seafood that is a rich source of iodine. Dairy products also contain iodine. Other good sources are plants grown in iodine-rich soil.
 Recommended Daily Dosage
- 0 - 6 months: 130 mcg/day
- 7 - 12 months: 130 mcg/day
- 1 - 3 years: 90 mcg/day
- 4 - 8 years: 90 mcg/day
- 9 - 13 years: 120 mcg/day
- Males age 14 and older: 150 mcg/day
- Females age 14 and older: 150 mcg/day
Note: Women who are pregnant or lactating need higher amounts.
 Iodine Deficiency
A goiter (enlarged thyroid gland) can be caused by eating both too little or too much iodine. The symptoms of either can also be the same: hypothyroidism, in which metabolism slows and weight and cholesterol increases; or hyperthyroidism where metabolism increases resulting in weight loss.
An iodine deficiency can inhibit brain development in a fetus, hence, women should ensure a reliable source of iodine.