The vitamin known as the sunshine vitamin is Vitamin D. It is called this because our bodies can synthesize it when our skin is exposed to sunlight, specifically ultraviolet B (UVB) rays. Vitamin D plays a crucial role in maintaining healthy bones by facilitating calcium absorption in the gut and regulating calcium levels in the blood. It also influences immune function and has been studied for its potential roles in various health conditions. Dietary sources of Vitamin D include fatty fish, fortified foods, and egg yolks, but sunlight exposure is the primary source for most individuals.