Selenium and Iodide

Too much selenium

toxicity is normally not from food sources, except Brazil nuts Can occur from using supplements for too long of a time Signs: hair loss, weakness, nausea, vomiting, cirrhosis

Goiter

1. Can cause pressure on the windpipe and difficulty breathing. 2. Will not significantly shrink once it has formed. Removal will require surgery. 3. More common in certain parts of Asia, Latin America and Africa

Sources of Iodine

1. Dairies use it as a sterilizing agent 2. Bakers use it as a dough conditioner 3. Iodized salt, yogurt, fat free milk

Functions of Selenium

1. Essential trace mineral 2. Aids an antioxidant enzyme 3. Spares Vitamin E; indirectly maintaining the health of the cell membrane4 4. Is a component of an enzyme that helps activate the thyroid hormone T3

Other concerns for Iodine deficiency

1. If a pregnant woman suffers iodide deficiency her body will use up what is available leaving the fetus to suffer. 2. The baby may be born with congenital hypothyroidism (formally known as cretinism). This is defined as stunted growth and intellectual development delays.

Thyroid gland and Iodine

1. Produces 2 hormones T4 and T3 which contain iodine molecules. 2. Roles of Thyroid hormone include regulating metabolic rate for all cells, heat production, as well as processes of cell growth and tissue differentiation.

Deficiency of Selenium

1. Selenium in food relies on the Se content in the soil (most places are adequate) 2.Symptoms: muscle pain and wasting, certain forms of heart damage, impairment of thyroid functioning (limited growth) and some cancer

Iodine deficiency

1. When iodide concentration in the blood is low, the thyroid cannot get the amount of iodide that it needs for proper function. 2. As a result cells of the thyroid enlarge in an effort to take up as much as possible. 3. This enlarged thyroid is called a goiter.

Upper limited of Iodine

1.1 mg thyroid hormone synthesis is inhibited

RDA for iodine

150 micrograms A half teaspoon or 2 grams of iodide fortified salt provides this. Most Americans get 190-300 micrograms

Food sources of Selenium

Fish Shellfish Eggs Other meats Brazil nuts Grains Seeds grown in Selenium rich soil

What is Iodine?

Iodine: element form Iodide: ion state, how its found in the body?

RDA for Selenium

RDA- 55 micrograms Daily Value- 70 micrograms Upper Limit- 400 micrograms Average adult intake- 105 micrograms