The active form of Vitamin D is known as cholecalciferol (D3) and is produced by the body when sunlight is absorbed through the skin. For this reason, in Canada people are often found to be deficient in vitamin D. A typical year in Canada only has one season that provides enough sunlight and heat to ensure adequate amounts of skin exposure to the sun. The rest of the year is mainly spent indoors or in long sleeves, pants, jackets with only the face and hands in direct sunlight. Even in the summer months, use of sunscreen (properly applied), can reduce vitamin D absorption by more than 90%!
As mentioned above, there are important uses of vitamin D as it pertains to our health. If we aren’t getting adequate vitamin D absorbed through the skin for 50-75% of the year, then the supplementation of active vitamin D3 can be a beneficial option to maintaining optimal health and for disease prevention.