I originally wrote this article in 2013, and I’ve updated it now with more research and to stress it’s importance in immunity. Everyone should take a Vitamin D supplement.  Yes I said EVERYONE. Why?  There are multiple reasons.  Optimizing your vitamin D levels should be at the top of the list for virtually everyone, regardless of your age, sex, color, or health status, as vitamin D deficiency has been linked to an astonishingly diverse array of common chronic diseases.  Let’s explore what happens in our bodies, and why I think it is CRUCIAL to check your levels with your physician and make sure your body has enough available Vitamin D3. Vitamin D is actually a group of fat-soluble secosteroids responsible for intestinal absorption of calcium and phosphate.  Basically it is a neuroregulatory steroidal hormone that influences THOUSANDS of gene interactions in your body.  One example of an important gene that vitamin D up-regulates is your ability to fight infections, as well as chronic inflammation. It produces over 200 antimicrobial peptides, the most important of which …