Essential Nutrition Precursor to Vitamin A Antioxidant Protection of Vitamins A &E A Dietary Supplement Vitamins Family Owned Since 1968 GMP Quality Assured Beta-Carotene is an essential nutrient found predominantly in algal species and in yellow, orange, and dark green vegetables. It is fat soluble and may serve as either an antioxidant or be converted to retinol (vitamin A) in the body based on physiological need.