The essential vitamin produced when the skin is exposed to sunlight is Vitamin D. This vitamin is critical for maintaining healthy bones and immune function. The skin synthesizes Vitamin D when ultraviolet B (UVB) rays from the sun strike it, triggering a biochemical process. People living in sunnier regions might obtain enough vitamin D through outdoor activities, while those in less sunny climates may require dietary sources or supplements. Understanding the importance of vitamin D and safe sun exposure practices can greatly contribute to overall health and well-being.