Nature's Bounty Vitamin D - the "Sunshine Vitamin" is an essential nutrient that the body creates by converting cholesterol in the body via sunshine. Supplementing with Vitamin D3 is an easy way to increase your daily intake of this important nutrient. Vitamin D by Nature’s Bounty may assist the immune system. In addition to immune support, getting a sufficient amount of Vitamin D is critical to building and maintaining strong bones in adults. It is essential for calcium absorption to help support healthy bones. Nature’s Bounty Vitamin D3 Softgels supplement the Vitamin D your body needs for overall health.