Why we study the obvious

A standard criticism of science, especially in areas you don’t agree with, is to quote the ‘obvious’ findings that scientists have wasted time and money checking.

Quite often, though, the obvious doesn’t happen.  Stuff has a story about a randomized trial of intensive weight-loss propaganda in people with Type II diabetes: the trial is being stopped early, after ten years, because it isn’t working.  People in the intervention group are losing weight, and improving their control of blood sugar, but they are still getting heart attacks and strokes at the same rate as the control group.

An earlier trial had given a lot of hope by showing that quite small increases in exercise and reductions in weight could stop pre-diabetic levels of insulin resistance progressing to full-blown diabetes.

The current trial is led by Professor Rena Wing, of Brown University, who is hardly a heretic on the general weight-loss message.  Her research focuses on ways to maintain weight loss, and when the trial started she said

“Getting people to lose weight is talked about as the best treatment for both preventing diabetes in people who are overweight and for treating individuals who already have the disease,” Wing said. “If the long-term data from the study support these approaches, it will make it easier to go to patients, insurance companies and public-policy makers and say, ‘Yes, weight loss works over the long run.’”

We don’t have the full details of results, which are still be analysed. However, the trial succeeded in getting people to about the same amount of weight as in the earlier diabetes prevention trial, and to keep the weight off.  There were also improvement in glucose control, in sleep apnea, and in general quality of life, which might be sufficient motivation for weight loss, but not in heart disease and stroke.   This was a large, well-funded, well-designed study, and I would have bet on the results being the other way.

There won’t be any shortage of people who don’t want to believe the results, and it will be interesting to see if any of them can come up with some useful explanation for why the other differences between treatment and control groups don’t translate to reductions in heart disease or stroke.  [There will also be plenty who are happy to just say the results are wrong without needing anything as difficult as an explanation]

Unless there is something the researchers have completely overlooked, this trial adds to the long list of things that improve blood test results but don’t provide the expected health benefits in Type II diabetes.