Vitamin E, Selenium and Healthy Horses Biochemists have studied vitamin E and selenium primarily for their crucial roles in limiting free radical damage in the body. Free radicals are reactive, unbalanced molecules produced during oxidation and other processes. Free radicals damage body tissues by changing the molecular structure of the cells. These free radicals are also removed by glutathione peroxidase, a selenium-containing enzyme. This is one of several ways in which vitamin E and selenium protect and spare each other in the body.
Research demonstrates that their nutritional value is raised when they are supplemented together.
Numerous factors, including pollution, heavy exercise, pregnancy, lactation, growth and high levels of dietary fat, increase the horse's needs for these nutrients. In the U.S., soils in the East, Northwest, and Great Lakes regions are selenium deficient. In some Midwestern and Southwestern states, local soils may contain excessive amounts of selenium. In these areas, contact your local feed consultant or county extension agent before supplementing selenium. Antioxidants are natural substances produced by the body or supplied in the diet.