Vitamin D is synthesized by the human body when sunlight hits our skin and interacts with cholesterol. The process, of course, is very complicated. It is estimated that when we are exposed to the midday summer sun for 30 minutes, wearing only a bathing suit our bodies make about 20,000 units of Vitamin D.
In Canada, from the month of September to May, the sun is too far away to allow this kind of reaction to take place. Lets face it, it is also too cold to be walking around in a bathing suit. While some of the products that we consume: milk, orange juice, and oily fish contain some Vitamin D, it is safe to say that many of us are either Vitamin D deficient or have levels on the low end of optimal.
People living in traditional cultures, like the Inuit and those who live in the northern areas of Europe ate a diet rich in foods such as oily fish and seal. These are loaded with Vitamin D and afforded them the Vitamin D needed to survive the long, cold, dark winters they were faced with.
Vitamin D is an extremely important player in our metabolism. It affects more than 200 genes and is found in most parts of the body. It aids in the absorption of calcium into our bones. Vitamin D is linked to immunity and may explain higher rates of influenza and common cold in the winter. Vitamin D also plays a role in preventing osteoporosis, certain cancers, cardiovascular disease, asthma, and multiple sclerosis among other things.
So, the question remains, do you know your Vitamin D level?