LIFENOW Calcium with Vitamin D3 Supplement- 60 TabletsCalcium plays an essential role in keeping the bones strong. But to maximize the calcium absorption and its function, Vitamin D3 is essential. Most of the Calcium that is consumed via food is in its inactive form and needs to be converted to an active form to perform its function properly. Thats where Vitamin D3 comes in. LIFENOW is one of the best brands for quality Calcium and D3 tablets in India. Vitamin D3 helps turn calcium into its active form.