I have a similar story in that I grew up on the ocean in Massachusetts and in the summer, never wore sun protection (yes, this is during the 50s and 60s), and never burned but developed a brown tan that could withstand any amount of sun whether I was out all day sailing, swimming, surfing, etc. We never thought of using sunscreen. I'm fair haired, fair skinned.

Fast forward to today, and I can go out in the sun extensively and develop nothing more than a tan. If it's early part of the warm season, I may get slightly red the first day, then it turns to tan and becomes the base that protects me for the rest of the season. I attribute this change to going VLCKD almost 8 years ago. I, too, like to get my vitamin D naturally but supplement with D3 as well. I, too, take a multi K (Koncentrated K) with ample amounts of K, K2. I believe all this is interrelated with good health, and D from the sun is best. I get a bit more nowadays living in No. Virginia, but still supplement when I'm not able to get sun with a healthy dose of D3 (5,000 IUs) from a good supplement producer. It's encouraging hearing Dr. Davis confirm the potential of reducing CAC scores. Patrick Theut is also one (a chemical engineer by trade) who has had tremendous success in this area using supplements.