Bone Builder Capsules provides 1,200 mg of calcium per day in an easy-to-swallow capsule form. Bone Builder Capsules features the same calcium-rich MCHC found in original Bone Builder, along with added vitamin D and magnesium for strong, healthy bones.With over one-half of the total body stores found in bone tissue, magnesium has been shown to play an important role in bone metabolism. Boron is a trace mineral that may support bone health through its involvement in vitamin D and estrogen metabolism. Vitamin D is an essential nutrient that helps stimulate calcium absorption and regulate calcium and phosphorus levels in the body.