NOW Foods Beta Carotene 25,000 IU provides natural beta-carotene from D. salina algae — a provitamin A carotenoid that the body converts to vitamin A on demand, making it a safe alternative to preformed retinol for those concerned about vitamin A toxicity from high-dose supplementation. Because conversion from beta-carotene to retinol is self-regulating (the body converts only as much as needed), it cannot cause the liver accumulation associated with excess preformed vitamin A. Natural beta-carotene also provides antioxidant protection in its unconverted form — protecting skin, lungs, and immune cells from oxidative damage. The D. salina algae source also provides a natural mixture of carotenoids including alpha-carotene and zeaxanthin for broader antioxidant support. Delivered in an oil-based softgel for optimal absorption. GMP-certified.