Selenium

Selenium’s job is to reduce peroxide free radicals, which are believed to cause aging and are implicated in various forms of cancer. It works synergistically with vitamin E as an antioxidant. It plays a vital role in thyroid function. Plants are the most common dietary source of this mineral. The amount of it that is in plant products depends on how much mineral was in the soil where this plant was grown. If the plant was grown in selenium-deficient soil, the food is going to be deficient also.

In the United States, the selenium content in plants can vary almost 200-fold from region to region. Meat and poultry tend to be more reliable sources of selenium, because animals are usually fed with supplements of this mineral.

High doses of iron, vitamin C and heavy metals can decrease the absorption of selenium.

The SELECT study was designed to see the effects of selenium and other antioxidants in the prevention of prostate cancer. After 5 years, the intervention group showed no difference from the controlled group, suggesting that there was no benefit from taking selenium.

However, there is a correlation between selenium levels in your blood and something called C-reactive protein, which is a measure of inflammation. The higher your C-reactive protein, the greater your inflammatory response. In some studies, the higher the selenium level in the blood, the lower your C-reactive protein, suggesting that selenium may reduce inflammation. This inflammatory response is thought to be part of the process of heart disease and cancer.

Beyond heart disease, there is an ongoing interest in selenium supplementation. Originally, the interest surfaced when about 180 men with HIV had a reduction in hospitalization with 200 micrograms of selenium. Supplementation may offer some protection from basal cell carcinomas, but an increased risk of squamous cell skin cancer. The take-home point is that we should concentrate on selenium-rich foods, not supplements.

Selenium deficiencies are rare in the United States, where intake is typically 100 to 250 micrograms per day. Deficiencies are on the rise, however. They are prevalent after a gastric-bypass surgery. As the number of Americans going for a gastric bypass surgery increases, the heart diseases associated with selenium deficiencies are on the rise.

Toxicity can exist, but it is usually at doses greater than 900 micrograms per day. Increased levels of selenium may increase the likelihood of glucose intolerance, which is one of the precursors of diabetes.

Daily Recommended Amounts

Infant, 0–6 months	15 micrograms
Infant, 7–12 months	20 micrograms
Child, 1–3 years	20 micrograms
Child, 4–8 years	30 micrograms
Male, 9–13 years	40 micrograms
Male, 14–70 years	55 micrograms
Female, 9–13 years	40 micrograms
Female, 14–70 years	55 milligrams

Good Food Sources

1 whole egg, boiled	13.55 micrograms
4 oz chicken breast, roasted	28 micrograms
1/4 cup sunflower seeds, raw	21.42 micrograms
1 sardine	48.48 micrograms
1 cup oats, cooked	18.95 micrograms
1 cup pasta, whole wheat, cooked	36.3 micrograms