Nutra Life Vitamin D3 1000iu Caps 60 Why use Vitamin D3 1000IU Plus Boron & Selenium? This powerful, one-a-day bone and immune system health formula blends a high-strength 1000IU of Vitamin D3 (the active form of Vitamin D) with important bone-supporting antioxidants. Vitamin D helps our bodies to absorb and use Calcium properly, which in turn helps to maintain healthy bone strength and density. Boron and Selenium are essential antioxidants that further support bone health. Recommended for Assisting Calcium absorption and maintaining strong, healthy bones in later life supporting a healthy immune system.