One big problem is lack of clinical evidence in trying to follow the natural, alternative health protocols and health substances, in contrast to the pharmaceutical research and clinical studies.
There is a lot of money on the line when it comes to pharmaceutical research so the studies are frequently manipulated or extrapolated in order to show the desired results. So most of the research on pharmaceuticals is worthless. Just look at how many FDA approved drugs have been found to be worthless or later to have unreported side effects.
Chemotherapy agents and related drugs are the biggest offenders. I am pretty sure I reported in earlier posts how the FDA approved drug Endostatin was made to appear effective by dropping patients who died or did not respond from the final results. This practice by the pharmaceutical companies was actually reported by a couple of doctors in the Journal of the American Medical Association (JAMA) back a while ago. I don't recall off hand what year the report was that I read. It was pretty much pre-Internet, but it should be easy to find in a medical library.