Beta-carotene, also called provitamin A, is a member of a group of plant-produced compounds called carotenoids, which serve as precursors to vitamin A. Beta-carotene is a potent antioxidant. The ultimate source of all vitamin A is from the carotenes, and beta-carotene has the highest vitamin A activity 1. Beta-carotene is particularly abundant in orange vegetables and fruit, and may be directly added to foods as a vitamin supplement 2.
Carotenoids may either be absorbed through the intestines intact, or be cleaved to form vitamin A prior to absorption. There is no Recommended Dietary Allowance (RDA) for beta-carotene or other provitamin A carotenoids. However, dietary provitamin A carotenoids have vitamin A activity that can be expressed as retinol activity equivalents (RAEs). The RDA for RAEs is 900 µg/day for men and 700 µg/day for women 3. Beta-carotene supplementation in humans is likely safe over long periods of time.