Vitamin D improves calcium absorption and helps build strong bones and teeth. Cow’s milk is fortified with vitamin D in Canada and is the main source of vitamin D in the Canadian diet. While our skin can make vitamin D when exposed to the sun’s UV rays (hence the name ‘sunshine vitamin’), this is limited during the winter in Canada. Other factors, such as sunscreen use, also limit vitamin D production. That’s why food sources of vitamin D matter throughout the year. Learn more about why cow’s milk is an important source of vitamin D in Canada.