Calcium Citrate (1000 mg) + Elemental Magnesium (100 mg) + Elemental Zinc (4 mg) + Vitamin D3 (200 IU) belongs to the group of medicines called nutritional supplements used to treat nutritional deficiencies such as calcium and vitamin D deficiency. A nutritional deficiency occurs when the body does not absorb/get enough nutrients from food. Vitamins are necessary for body development and the prevention of diseases.