Selenium Monograph

Pharmacokinetics Selenium levels in the body are largely dependent on the amount of the element in the diet. However, the form of selenium within the diet has an important influence on absorption. L-(+)selenomethionine is readily absorbed from the gastrointestinal tract and is significantly better absorbed and retained in the body than inorganic selenium in the form of selenite. L-(+)selenomethionine has slower whole-body turnover compared with selenite, an attribute that provides efficient use of the selenium contained in the complex methionine. In rats, dietary supplementation with selenomethionine, selenite, and selenocysteine showed the highest increase in tissue selenium levels was accomplished with selenomethionine, with tissue selenium increase most significant in muscles.