Vitamin D3: The Sunshine Vitamin Your Body Needs Vitamin D3, also known as cholecalciferol, is often called the “sunshine vitamin” — and for good reason. It’s a vital nutrient that the body produces when the skin is exposed to sunlight. Unlike other vitamins, Vitamin D3 functions more like a hormone, playing a crucial role in multiple bodily systems. From supporting strong bones to boosting immunity and mood, Vitamin...