skin produces vitamin D3 when exposed to UVB sunlight
Vitamin D synthesis is the process by which the skin produces vitamin D when exposed to ultraviolet B (UVB) rays from sunlight. This process involves the conversion of 7-dehydrocholesterol in the skin to cholecalciferol (vitamin D3), which is then further metabolized in the liver and kidneys to its active form, calcitriol. This active form of vitamin D is crucial for calcium absorption, bone health, and immune function.