ACE your immune support. Selenium and vitamins A, C, and E are more effective when taken together than individually. Combined, they provide a highly active antioxidant complex that helps protect our body from free radical damage. Beta-carotene quenches single oxygen molecules; vitamin C guards tissue and blood components; vitamin E protects cell membranes; and selenium serves as a vital building block for glutathione peroxidase, an important member of the antioxidant family. Antioxidants, specifically Cardio ACES - vitamins A, C, E, and selenium - also play an important role in heart health.