Which vitamin is essential for calcium absorption?

Vitamin D is essential for calcium absorption because it plays a crucial role in the regulation of calcium and phosphate in the body. When vitamin D is present, the intestines become more effective at absorbing calcium from the diet. It helps to increase the expression of calcium-binding proteins in the intestinal lining, which facilitates the uptake of calcium into the body. Moreover, vitamin D also contributes to maintaining adequate levels of calcium in the blood, which is vital for numerous bodily functions, including bone health and muscle function.

While the other vitamins listed are important for various bodily functions, they do not directly contribute to calcium absorption in the same way that vitamin D does. Vitamin A is involved in vision and immune function, vitamin B12 is essential for nerve function and the production of DNA and red blood cells, and vitamin C plays a role in collagen synthesis and antioxidant defense. However, none of them have a direct role in promoting the absorption of calcium from food.