So what does that mean for your health?
Vitamin D's major role in the body is to carry calcium from our digestive tracts through our blood and into our bones, keeping them strong. When we don't have enough vitamin D, even if we consume lots of calcium, our bones can become weak resulting in conditions like rickets (in children) or osteoporosis (in adults).
Vitamin D is not only important to bone health, but recent research is starting to link vitamin D with potential benefits in heart disease, diabetes and MS though results are not yet conclusive.
The biggest point I'm trying to make here is the sun is where it's at (the vitamin D that is), but with concerns about skin cancer (vitamin D cannot be converted through sun screen) and the fact we get sunshine consistently for only a few months of the year in Canada, it's not a bad idea to look at ways to improve your intake.
Major food sources of vitamin D include fortified foods like milk, margarine and orange juice. Eggs and fish such as tuna and salmon also contain vitamin D. Getting outdoors will help you get more vitamin D but it isn't a bad idea to consider a vitamin supplement during the winter months.
An average person needs about 600IU of vitamin D/day. If you have bone related issues, be sure to speak with your doctor about your specific needs.