The Importance of Vitamin E and Selenium


Vitamin E and selenium are powerful protectors of muscle as well as immune function.

Vitamin E and selenium (Se) are familiar nutrients to most horse people.  They are among the most common deficiencies in unsupplemented animals – and also the only two where deficiency diseases are still routinely seen.  Suboptimal levels also impact health and performance, and levels below those will trigger full blown deficiency syndromes.

E and Se are often supplemented together, but contrary to popular belief they do not actually work together, nor is their absorption from the intestinal tract interrelated in any way. However, they complement each other to provide broad spectrum protection to the body’s cells.

E and Se are both important antioxidants. Vitamin E works to prevent fats within membranes from oxidative damage.  Se, as part of the glutathione peroxidase enzymes, works to protect the internal watery portions of cells from free radical injury. Free radicals are a by-product of immune system activity, and of cells generating energy for work or cell division.

Vitamin E and selenium status is documented to significantly impact:

  • The nervous system
  • Muscular function
  • Fertility/sperm quality
  • Antibody levels in colostrum
  • Immune function
  • Red blood cell integrity in exercising horses
  • Heart health
  • Cancer surveillance


Selenium is also integral to the enzyme which converts the inactive form of thyroid hormone (T4) to the active T3.


In most areas of the US and Canada, selenium is barely adequate to frankly deficient.  Horses not being maintained on pasture have extremely low levels of vitamin E in unsupplemented diets. Vitamin E added to feeds or multi-ingredient supplements often acts more like a natural preservative than a supplement because even stabilized forms of the vitamin can breakdown easily.

Horses absorb inorganic selenium (e.g. sodium selenate) well, but absorption of this form may be reduced by high levels of competing minerals in the diet. For this reason, some or all of the selenium supplement should be in the form of high selenium yeast.


As above, vitamin E can be unstable. I prefer to supplement it separately. Because this is a fat-soluble vitamin it is best given dissolved in fat.  If your supplement is powdered, mix it into some oil or sprinkle it on top of oil top dressed on the feed.


Vitamin E and selenium are two of the most important and the most often deficient nutrients in the horse’s diet.  Make sure your horse’s intake is adequate.
Uckele Health & Nutrition, maker of CocoSoya®, offers Vitamin E and Selenium formulas. 


E-Se 10X provides concentrated natural Vitamin E and organic Selenium Yeast.  When combined, these two important antioxidants work synergistically to more powerfully support a healthy immune system, protect the cells and tissues of the horse’s body, and neutralize the damaging effects of excessive oxidative stress and free radicals.

Liquid E-50 provides high strength liquid Vitamin E that protects from damaging free radicals that can weaken cells and tissues.  In addition to powerful antioxidant properties, Vitamin E promotes healthy immune, cardiovascular, circulatory, neuromuscular, and reproductive functions.

Selenium Yeast Blend is an 0rganic chelated Selenium yeast blend in a palatable Brewer’s Yeast base. Commonly deficient in horses, Selenium supports muscle tissue, the heart, and the nervous system.  It also promotes a healthy immune system by neutralizing the damaging effects of excessive oxidative stress and free radicals.  Perfect for feeding Selenium without adding Vitamin E.


About Dr. Kellon
Dr. Eleanor Kellon, staff veterinary specialist for Uckele Health & Nutrition, is an established authority in the field of equine nutrition for over 30 years, and a founding member and leader of the Equine Cushings and Insulin Resistance (ECIR) group, whose mission is to improve the welfare of horses with metabolic disorders via integration of research and real-life clinical experience.  Prevention of laminitis is the ultimate goal.

Uckele Health & Nutrition, maker of CocoSoya, is an innovation-driven health company committed to making people and their animals healthier.  On the leading edge of nutritional science and technology for over 50 years, Uckele formulates and manufactures a full spectrum of quality nutritional supplements incorporating the latest nutritional advances.