Vitamin D3 contains 1,000 IU of natural vitamin D3 per softgel. Vitamin D, also known as the “sunshine vitamin,” is an essential vitamin that plays many important roles in the proper functioning of the body. Though classified as a vitamin, vitamin D is actually a key regulatory hormone for calcium and bone metabolism. Adequate vitamin D status is essential for ensuring normal calcium absorption and maintenance of healthy plasma calcium levels. Besides bone support, vitamin D has many other roles in the body, including modulation of cell growth, neuromuscular function, immune function and inflammatory support.