You already know vitamin D is synthesized when your skin is exposed to the sun, but also rays from the sun can cause burns, so is sun exposure good or bad? Vitamin D3 plays many roles in our body. It helps with fighting infections, maintaining blood pressure and bone density, and preventing many autoimmune diseases. Unfortunately sunscreens block the UVB rays that help to create D3 and according to Mercola.com, these rays are most prevalent during the middle of the day when t