The vitamin primarily acquired through sunlight is Vitamin D. This nutrient is unique because the body can produce it when the skin is exposed to ultraviolet (UV) rays from the sun. Vitamin D plays a crucial role in maintaining bone health by aiding in the absorption of calcium and phosphorus. It also supports immune function and has been linked to various health benefits. Many people may require supplementation, especially those living in areas with limited sun exposure or those with darker skin tones, which produce less vitamin D in response to sunlight.