Vitamin C is a water-soluble vitamin with a variety of antioxidant, anti-inflammatory, and microvascular effects. Although it is popularly used in common cold, fortifying the immune system, Collagen synthesis for joint, hair, skin, and nail care, Increasing absorption of Iron, and preserving eye function. Vitamin D3 is a fat-soluble pro-hormone also known as Cholecalciferol, produced by the body when exposed to sunlight. It is known for the vital role it plays in the maintenance of strong bones and teeth (this it does by regulating the absorption of Calcium and phosphorus in the blood), Reducing flu risk- (the presence of the vitamin D receptor on almost all cells of the immune system gives a hint to the significant role vitamin D plays in immune function). Supporting immune, brain and nervous system health.