process converting vitamin D into its active, calcium-regulating form
Vitamin D metabolism refers to the process by which the body converts vitamin D from sunlight or dietary sources into its active form, which is crucial for calcium absorption and bone health. This involves two main steps: first, vitamin D is converted to calcidiol in the liver, and then to calcitriol in the kidneys, which is the biologically active form that helps regulate calcium and phosphate levels in the blood.