A vitamin D metabolite is a form of vitamin D that has undergone chemical changes in the body. The most well-known metabolites are calcidiol and calcitriol. These compounds are produced when the body processes vitamin D from sunlight, food, or supplements, playing crucial roles in maintaining health. Calcitriol, the active form of vitamin D, helps regulate calcium and phosphate levels in the body, which are essential for bone health. Adequate levels of vitamin D metabolites are important for overall well-being, as they support immune function and may influence mood and other bodily processes.