Life Extension Vitamin D3 25mcg (1000 IU), 90 softgelsWhole body health all star Your body uses vitamin D to keep you healthy and thriving. This supplement delivers 25 mcg of cholecalciferol (vitamin D3), a form thats more efficient at maintaining healthy D levels than other vitamin D supplements. Immune system and heart health support Vitamin D3 helps your body combat everyday and seasonal immune challenges, encouraging a robust immune response. Vitamin D benefits heart health, and endothelial health.