Iodine - Benefits, Deficiency Symptoms and Food Sources

What is Iodine?

Iodine was discovered by B. Courtois in 1811 in Paris, France. Most of the iodine in the body occurs in the thyroid gland. Iodine in the thyroid gland is necessary for the formation of thyroid hormones. Most of the Earth's iodine is found in its oceans.

If iodine is in contact with the skin it can cause lesions, and iodine vapour is extremely irritating to the eyes and mucous membranes.

Uses and Benefits of Iodine

Iodine is an essential component of the thyroid hormones, triiodothyronine (T3) and thyroxine (T4) and is therefore essential for normal thyroid function. To meet the body's demand for thyroid hormones, the thyroid gland traps iodine from the blood and converts it into thyroid hormones that are stored and released into the circulation when needed. Iodine may decrease the effectiveness of some thyroid drugs. Taking high doses of kelp could provide too much iodine and interfere with the actions of some thyroid drugs.

Recommended Dosage of Iodine

Even if one is on a severely restricted salt diet for high blood pressure, he or she probably don't require extra iodine, though they can safely take 150 mcg a day.

The following are the recommended daily allowances for iodine:

• Infants 40 - 50 micrograms
• Children
• one to three years 70 micrograms
• four to six years 90 micrograms
• seven to 10 years 120 micrograms
• 11+ years 150 micrograms
• Pregnant women 175 micrograms
• Lactating women 200 micrograms
• Adult men & women 100 - 200 micrograms

Deficiency Symptoms of Iodine

Iodine deficiency is caused by a lack of iodine, a chemical element essential to the body's physical and mental development, in a person's diet.

In the early part of the 20th century, iodine deficiency was quite common in the United States and Canada. Goiter, or enlargement of the thyroid gland, is usually the earliest symptom of iodine deficiency. Iodine deficiency may eventually lead to hypothyroidism, which causes a variety of symptoms including fatigue, weight gain, weakness and/or depression. Severe iodine deficiency during pregnancy or infancy causes cretinism, a condition characterized by hypothyroidism leading to failure of the thyroid gland and/or severe mental retardation, stunted physical growth, deafness, and spasticity.

Rich Food Sources of Iodine

Vegetables may also be good sources of iodine, provided these are grown in iodine-rich soil. Seaweeds like lato, gamet, balbalulang, and seafoods are very good sources of iodine. Seafood is rich in iodine because marine animals can concentrate the iodine from seawater. Certain types of seaweed (e.g., wakame) are also very rich in iodine.