vitamin d3 is also known as cholecalciferol, is a fat-soluble vitamin that plays a crucial role in regulating calcium and phosphorus levels in the body. It's synthesized in the skin when exposed to sunlight and is also found in certain foods like fatty fish, egg yolks, and fortified dairy products. In food products, vitamin D3 is added as a fortificant to increase dietary intake and promote bone health, immune function, and overall well-being