The vitamin that the body synthesizes from sunlight is vitamin D. When skin is exposed to ultraviolet (UV) rays from sunlight, a chemical reaction occurs that produces vitamin D. This vitamin is crucial for maintaining healthy bones and teeth, as it aids in calcium absorption. Additionally, vitamin D plays a role in immune function and has been associated with various health benefits. Due to limited sun exposure in some regions, dietary sources of vitamin D or supplements may be necessary to maintain adequate levels.