Which vitamin is added to milk for its essential role in growth and bone repair?

Vitamin D is added to milk primarily because of its crucial role in promoting calcium absorption and maintaining bone health. This vitamin facilitates the intestinal absorption of calcium and phosphate, which are both essential for the development and strength of bones. Without adequate vitamin D, the body cannot effectively absorb calcium, leading to potential issues such as rickets in children or osteomalacia in adults.

The fortification of milk with vitamin D is a public health measure aimed at preventing these bone-related health issues, especially in populations that may have limited sun exposure necessary for the body's natural production of vitamin D. The addition of this vitamin helps ensure that individuals, particularly children, receive sufficient amounts to support proper growth and bone repair throughout their developmental years.