So the simplest solution is to take selenium as a supplement. The RDA for children has yet to be established. Anything over 200 micrograms is considered dangerous. In large doses, selenium is toxic. Unfortunately, the selenium in supplements does not appear to be as well absorbed and used by the body as the traces found in food.
Research shows that foods high in protein are usually the highest in selenium.
These are beef, fish and poultry. The best source, though, is Brazil nuts. Just two per day will provide more than the recommended dosage. Early settlers in the U.S. applied it as a saddle-sore salve for horses. Now the plant is gaining popularity as an immune booster that prevents the first signs of sniffles and sore throats from developing into fully fledged colds.