What is one of the main functions of calcitriol in calcium metabolism?

Calcitriol, the active form of vitamin D, plays a crucial role in calcium metabolism by promoting the absorption of calcium in the intestines. When calcium levels in the blood are low, the body synthesizes calcitriol to increase the efficiency of calcium uptake from dietary sources. This function is essential for maintaining adequate calcium levels, which are vital for numerous bodily functions, including bone health, muscle function, and nerve transmission.

In addition to its role in enhancing intestinal absorption of calcium, calcitriol also works synergistically with parathyroid hormone to maintain calcium homeostasis. While it affects various aspects of calcium regulation, its primary and notable function in the context of calcium metabolism is facilitating its absorption in the gastrointestinal tract. Understanding this mechanism helps to clarify how the body regulates calcium levels, especially when dietary intake might be insufficient.