GO CALCIUM 1-A-DAY NATURAL SOURCE is the perfect synergy of Calcium, Vitamin D3 and Vitamin K2, which work together for superior absorption and bone health. Each capsule contains 500mg of elemental Calcium along with other important bone health minerals from natural, sustainable seaweed. The addition of Vitamin K2 and Vitamin D3 ensures the advanced absorption and binding of Calcium into the bones which helps to ensure bones stay strong, healthy and less likely to fracture and deteriorate.