Country Life Calcium Magnesium Zinc with Vitamin D supplement is the ultimate blend for bone health.** The Target-Mins® formula is made with specific free-form amino acids and uses a calcium to phosphorus and calcium to magnesium ratio of 2:1 to support calcium utilization and the body’s availability of calcium.** Vitamin D helps the body absorb calcium, which is crucial for healthy bones, and magnesium helps regulate hundreds of enzyme systems in the body, including healthy muscle and nerve function.** This healthful blend contains 1000 mg calcium, 500 mg magnesium, 500 mg phosphorus and 200 I.U. (5 mcg) vitamin D, plus, 25 mg zinc per serving to support immune health.**