Selenium (citrate) – Soil levels of this trace mineral can dramatically vary depending on state and region of the United States. Generally, those areas with the highest amounts of selenium in the soil have lowest disease rates. Selenium plays a variety of functions in the body, and is part of the antioxidant system that protects cell membranes from lipid per-oxidation. Vitamin E and Selenium work synergistic functions together and are attributed as the anti-aging and longevity duo. *Selenium is a natural antioxidant that delays the oxidation of polyunsaturated fatty acids and preserves the elasticity of tissue. Selenium is required for the production of certain prostaglandins, which promote healthy blood flow. In synergy with vitamin E, selenium promotes healthy growth and fertility, and improves the function of certain energy producing cells. Selenium also provides support for the immune system.