Persons with Type 2 diabetes have an increased risk of heart disease and stroke. They are usually overweight. A study of about 5000 persons with Type 2 diabetes who were overweight or worse asked if eating less and exercise — causing weight loss — would reduce the risk. of heart disease and stroke. The difficult treatment caused a small amount of weight loss (5%), which was enough to reduce risk factors. The study ended earlier than planned because eating less and exercise didn’t help: “11 years after the study began, researchers concluded it was futile to continue — the two groups had nearly identical rates of heart attacks, strokes and cardiovascular deaths.”
Heart disease and stroke are major causes of death and disability. Failure of such an expensive study ($20 million?) to produce a clearly helpful result is an indication that mainstream health researchers don’t understand what causes heart disease and stroke. Another indication is that the treatment being studied (eating less and exercise) was popular in the 1950s. Mainstream thinking about weight control is stuck in the 1950s. It is entirely possible that greater weight loss — which mainstream thinking is unable to achieve — would have reduced heart disease and stroke. If you understand what causes heart disease and stroke, your understanding may lead you to lines of reasoning less obvious than people with diabetes are overweight –> weight loss treatments).
One of the study organizers — Rena Wing, a Brown University professor who studies weight control — told a journalist “you do a study because you don’t know the answer.” She failed to add, I’m sure, that wise people do not give a super-expensive car to someone who can’t drive. You should learn to drive with a cheap car. Allowing ignorant researchers to do a super-expensive study was a mistake. To learn something, do the cheapest easiest study that will help. (As I have said many times.) You should not simply do “a study”. This principle was the most helpful thing I learned during my first ten years as a scientist. In this particular case, I doubt that a $20 million study was the cheapest easiest way to learn how to reduce heart disease and stroke.
I made to work that makes no progress on major health problems is another sign of the lack of understanding reflected in the failure of this study. I have never seen this lack of understanding — which has great everyday consequences — pointed out by any science blogger or science columnist or science journalist, many of whom describe themselves as “skeptical” and complain about “bad science.”