Bone Builder with Magnesium Glycinate features the same MCHC found in original Bone Builder®, but with the addition of 200 mg of magnesium per serving. Features a 2:1 ratio of calcium to magnesium for optimal absorption. Magnesium plays important roles in bone metabolism, with over one-half of the total body stores of magnesium found in bone tissue. Magnesium is provided as bis-glycinate-a revolutionary, fully reacted amino acid chelate produced by a unique, patented process for enhanced absorption. Vitamin D is an essential nutrient that helps stimulate calcium absorption and regulate calcium and phosphorus levels in the body.