100% Natural E-400iu Mixed Tocopherols & Selenium vitamin E and selenium are synergistic (they each increase the benefit of the other). What makes this formula special is the volume of Beta, Delta, and Gamma tocopherols added to the d-Alpha. It covers a far wider range of benefits than you standard natural Vit E. Both vitamin E and selenium are antioxidants, preventing or at least slowing aging and hardening of tissues through oxidation. Selenium is critical for the production of glutathione peroxidase, the body’s primary antioxidant that is found in every cell. Men appear to have a greater need for selenium. Almost half their body’s supply concentrates in the testicles and portions of the seminal ducts adjacent to the prostate gland. Also, selenium is excreted with seminal fluid.