Which vitamin is added to milk and is essential for building healthy bones?

Vitamin D is essential for building healthy bones as it plays a critical role in calcium absorption in the body. Calcium is a key mineral necessary for maintaining bone density and strength. When vitamin D is added to milk, it enhances the nutritional value of the milk by ensuring that consumers, especially children and adolescents who are in crucial stages of bone development, receive adequate levels of this vitamin. Without sufficient vitamin D, the body struggles to absorb calcium effectively, leading to potential bone health issues.

In the context of other vitamins, while vitamin C is important for immune function and collagen production, and vitamin A is vital for vision and skin health, neither plays a direct role in bone mineralization like vitamin D does. Vitamin B12 is primarily associated with red blood cell formation and neurological function rather than bone health. As a result, vitamin D stands out for its specific importance in the context of bone building when it is enriched in milk.