Consuming food rich in selenium can ward off the occurrence of this health problem.People living in regions deficient in soil Selenium must take supplements to protect themselves from occurrence of this condition.The recommended dietary allowance for selenium is 55-60 mcg per day for an adult.Pregnant women require 60 mcg of Selenium and lactating mothers require 70 mcg of selenium per day.Inclusion of seafood, garlic, mushroom and Brazil nut (which is the richest source of selenium) in diet can help in preventing the onset.