Calcium.

Milk tastes warm. No, I didn't grow up drinking milk that had been sitting out until it reached room temperature... It just tastes warm. This was the reason I never drank milk growing up, and why I still can't bring myself to enjoy a glass of cold milk. It just doesn't feel right, I can't describe the flavor, but it tastes like it's supposed to be warm. It's mostly not crisp enough to be cold. But warm milk is the best (especially with a little cinnamon). It's yummy, yummy, yummy! I like it, and my bones like it.