SELENIUM

Description

Selenium is involved in certain enzymatic reactions and is essential to the proper functioning of the thyroid gland. Its strong antioxidant effect protects cell membranes and helps neutralize toxic substances.

It also controls the use of vitamin C and can replace vitamin E in some of its functions.

Selenium may help protect against cancer, heart disease, arthritis and AIDS.

Sources

Brazil nuts are a major source of selenium since only one nut is enough to meet the daily requirement.

Other foods that are rich in selenium are seafood, organ meats, meats, poultry, fish, whole grains, dairy products and eggs.

The amount of selenium in foods is based on whether or not they are grown in selenium-rich soil.

Approximate selenium content
 Food  Portion  Content
 Beef liver 85 g 28 mcg
 Brazil nuts 7 543 mcg
 Canned light tuna 85 g 65 mcg
 Clams 85 g 41 mcg
 Egg 1 14 mcg
 Herring, marinated 85 g 50 mcg
 Food  Portion  Content
 Lobster 85 g 36 mcg
 Milk 250 mL 8 mcg
 Oysters 6 54 mcg
 Pork, loin 85 g 39 mcg
 Ricotta cheese 250 mL 41 mcg
 Whole wheat bread 250 mL 85 mcg

Recommended Daily Allowance (RDA)

Recommended average daily nutrient intake that is sufficient to meet the nutrient requirements of nearly all (97 to 98%) healthy individuals in each age and gender group. The RDA should only be used as a guide for daily individual intake.

Selenium requirements
 Age  Men   Women 
 1-3 years 20 mcg 20 mcg
 4-8 years 30 mcg 30 mcg
 9-13 years 40 mcg 40 mcg
 14-18 years 55 mcg 55 mcg
 Age  Men   Women 
 19-50 years 55 mcg 55 mcg
 > 50 years 55 mcg 55 mcg
 Pregnancy   +5 mcg
 Breastfeeding   +15 mcg

The average Canadian’s intake is about 200 mcg per day.

Deficiency

Selenium deficiency is rare. It can cause a weakened immune system, heart disease, nail discoloration and muscle weakness.

Toxicity

Too much selenium can damage, rather than protect, the cells. The maximum safe dose is 400 mcg per day.

Toxicity is characterized by neurological disorders, tooth decay, skin inflammation, diarrhea, fatigue, irritability, garlic breath, nausea, vomiting and loss of hair, nails and teeth.

Supplements

Supplements are not recommended as they can be toxic and daily intake is easily reached through food. Doses that exceed 200 mcg per day should be avoided and are not recommended.

Watch what you eat. Nutrition has a significant impact on health!