Vitamin D is naturally produced by the body when exposed to direct sunlight. The actual exposure to UV rays and the synthesis of vitamin D depend on many factors, such as:

• Seasons
• Location
• Time
• Age
• Smog
• Skin darkness

Vitamin D is naturally present in foods such as vitamin D2 (Ergocalciferol) and vitamin D3 (Cholecalciferol), but it can also be provided in the form of supplements. Vitamin D contributes to the normal function of the immune system and muscles, as well as the maintenance of normal bones, teeth, and the normal absorption/utilization of calcium and phosphorus.