Calcium metabolism refers to the processes that regulate the levels of calcium in the body, which is essential for various functions, including bone health, muscle contraction, and nerve signaling. The body maintains calcium balance through dietary intake, absorption in the intestines, storage in bones, and excretion through the kidneys. Hormones such as parathyroid hormone and calcitonin play crucial roles in calcium metabolism. Parathyroid hormone increases calcium levels in the blood by promoting bone resorption and enhancing intestinal absorption, while calcitonin lowers blood calcium levels by inhibiting bone resorption. This balance is vital for overall health.