I don't believe that anyone should pop a supplement or a drug to try to cover up a problem - that is just chasing a cure in a bottle without addressing the underlying causes, and in that respect it could be likened to the overall philosophy of using mainstream drugs to manage symptoms instead of illness. On the other hand, there is absolutely no comparison to supplementing with a natural item to correct a deficiency versus taking unnatural drugs.
I try to point out that taking supplements without establishing a good health foundation is akin to trying to put a hasty patch ot two on a leaky roof which sits ontop of a building with a crumbling foundation. At best you may get some relief, but if a bad storm (disease) comes along, then you are ill equipped to ward it off.
See:
Building a Foundation for Better Health and Longevity
It might be prudent to follow the money when it comes what has been recently reported in India. As I pointed out in a response in The Times of India I posted, the article quoted doctors who said that the solution was mandatory Vitamin D fortification of foods. The article also blamed pollution for the vitamin D deficiency. So, instead of addressing the pollution and toxins, mandate fortifcation of processed foods with artificial vitamin D. Hogwash!
I will grant you that it very well could be that supplementing with larger amounts of Vitamin D without addressing other health issues and having an overall healthy diet and lifestyle might in some instances be detrimental. The same is likely true of other nutrients. On the other hand, I think that a general warning against vitamin D supplementation, or supplementation with any reasonable amounts of essential natural vitamins, minerals or other nutrients, would cause far more harm than benefit.
I don't think you will find any articles by John Cannell published on any of the self serving websites or in the self-created publications of Trevor Marshall, who is no Galileo (who had no financial stake in whether or not the earth was at the center of the universe). Regardless of anything published by John Cannell, there have been literally hundreds of studies on Vitamin D and, contrary to what you posted earlier, these studies did not suddenly pop up. If you go to PubMed you will find 48,216 entries for vitamin D which date all the way back to 1922.
Even the studies on Vitamin D which have been published recently are in many instances the culmination of studies that have been ongoing for years. Unlike Marshall, who has a patented protocol to push and profit from, the funders of many of those studies in many instances have not had such an agenda or financial stake in the outcome. I also note that Marshall has yet to provide any definitive in vitro proof of his contention about vitamin D, much less in vivo proof.
Actually, I am all in favor of scientific studies. Unbiased and properly conducted ones which are not funded and directed by those who have something to gain from the study results - as Marshall clearly does. I have great respect for John Cannell and the Vitamin D council and I note that Cannell has no products or protocols that they seek to personally gain from.