NOW Foods Vitamin A & D delivers two essential fat-soluble vitamins in a single softgel — providing 10,000 IU of preformed Vitamin A (retinol) alongside 400 IU of Vitamin D for synergistic immune, vision, and bone support. Preformed Vitamin A is the most directly usable form, supporting immune barrier function, vision health (particularly night vision), skin integrity, and normal cellular differentiation. Vitamin D is essential for calcium absorption, immune regulation, and bone mineralization. These two fat-soluble vitamins work together to regulate immune gene expression and maintain epithelial tissue — the body's first line of defense against pathogens. NOW Foods delivers both in an oil-based softgel for maximum absorption of these fat-soluble nutrients, manufactured in their GMP-certified facility with batch testing for potency.