What is Selenium for?
Selenium is a mineral. It is taken into the body in water and foods. People use it for medicine.
Most of the selenium in the body comes from the diet. The amount of selenium in food depends on where it is grown or raised. Crab, liver, fish, poultry, and wheat are generally good selenium sources. The amount of selenium in soils varies a lot around the world, which means that the foods grown in these soils also have differing selenium levels. In the U.S., the Eastern Coastal Plain and the Pacific Northwest have the lowest selenium levels. People in these regions naturally take in about 60 to 90 mcg of selenium per day from their diet. Although this amount of selenium is adequate, it is below the average daily intake in the U.S., which is 125 mcg.
Selenium is used for diseases of the heart and blood vessels, including stroke and “hardening of the arteries” (atherosclerosis). It is also used for preventing various cancers including cancer of the prostate, stomach, lung, and skin.
Some people use selenium for under-active thyroid, osteoarthritis, rheumatoid arthritis (RA), an eye disease called macular degeneration, hay fever, infertility, cataracts, gray hair, abnormal pap smears, chronic fatigue syndrome (CFS), mood disorders, arsenic poisoning, and preventing miscarriage.
Selenium is also used for preventing serious complications and death from critical illnesses such as head injury and burns. It is also used for preventing bird flu, treating HIV/AIDS, and reducing side effects from cancer chemotherapy.
What is Selenium Possibly Effective for?
Preventing lower than normal levels of selenium (selenium deficiency).
• HIV/AIDS. There is contradictory evidence about the effect of selenium supplements on HIV.
• Arthritis (osteoarthritis). Low selenium levels seem to be linked with an increased risk of developing osteoarthritis. But it’s not known whether selenium supplements can prevent osteoarthritis.
• Colorectal cancer. Evidence is conflicting about the effect of selenium on colorectal cancer.
• Esophageal cancer. Taking selenium supplements does not seem to significantly decrease the risk of esophageal cancer.
• Stomach cancer. Taking selenium in combination with vitamin C and vitamin E long-term (for about 7 years) does not seem to reduce the risk of developing precancerous stomach sores.
• “Hardening of the arteries” (atherosclerosis).
• Rheumatoid arthritis.
• Macular degeneration (eye disease).
• Hay fever.
• Gray hair.
• Mood disorders.
• Chemotherapy side effects.
• Swelling after surgery.
• Abnormal pap smears.
• Chronic fatigue syndrome (CFS).
• Bird flu.
• Preventing miscarriage.
• Overall cancer risk.