New Roots Herbal Vitamin D3 - 2500 IU - Vitamin D3 is the biologically active form of vitamin D. When combined with sufficient calcium, a healthy diet, and an active lifestyle, it can help reduce the incidence of osteoporosis. Each easy swallow softgel of Extra Strength Vitamin D3 (cholecalciferol) contains 2,500 IU of this critical vitamin for good health. This is the current maximum dosage recommended by Health Canada without a prescription to help prevent vitamin D3 deficiency.