The more I see these sorts or articles flooding the airwaves, the more I am convinced that it is part of a deliberate campaign to lead people down the right path. Mercola is right to suggest that we shouldn't all go run out and pop vit d pills, but rather, get sun. but, his view of blood testing is way over simplistic. by just testing 25D, you get an imcomplete picture. Need to look instead at the ratio between 25D and I,25D to know whether your vit d receptors are blocked. if blocked, taking vitamin d and even sunbathing will slowly degrade your immune system. and, this is not an isolated problem for a minority of people. it is extremely common. the degree of blockages varies.