Weight loss won’t prevent diabetes
Posted by medconsumers on January 15, 2012
Rare is the public announcement that a long-standing medical recommendation has been found to be impossible to follow. That’s what happened—albeit unofficially— at a recent press briefing when Richard Kahn, PhD, announced that weight loss is not the sure-fire preventive measure for avoiding diabetes 2. Studies show that hardly anyone can lose enough weight to meet the universally recommended goal. And even those who get there halfway usually regain the weight within a few years.
That won’t come as a surprise to anyone has ever tried dieting. What made this press briefing noteworthy, however, is the fact that Dr. Kahn was the chief scientific and medical officer of the American Diabetes Association for 25 years. His study raises questions about the centerpiece of the ADA’s standard diabetes prevention message: “Maintain a healthy weight “(along with increased physical activity). This is the advice that is also given to people diagnosed with prediabetes, a newly created “disease” that indicates they almost have diabetes 2 (more on that later). According to the ADA, which receives funding from the pharmaceutical industry, there are 79 million Americans who have prediabetes. All are likely to be put on long-term drug therapy once the weight-loss attempts fail or never get off the ground.
At the press briefing, Dr. Kahn, now a professor of medicine at the University of North Carolina, Chapel Hill, described his paper in this month’s issue of the public policy journal Health Affairs, which is primarily devoted to diabetes. He has based his conclusion about weight loss on the very clinical trials that set the standard for diabetes prevention. Perhaps Dr. Kahn is the first to notice that most of the study participants, all of whom were initially either overweight or obese, regained the weight after the trials were over.
“When you look at the published studies, you see that a substantial amount of weight loss is necessary and hardly anyone can meet the intended goal, explained Dr. Kahn. “People who participate in the standard community weight loss programs lose about 3-4% of their body weight, but they don’t get an appreciable delay in the onset of diabetes until they reach 7.5% weight loss. So you see they are not coming close to delaying or preventing diabetes.”
Based on the best of the diabetes prevention trials, here’s an estimate from Dr. Kahn’s paper for what a 4% weight loss would actually do for people in terms of health and cost-effectiveness: “If overweight or obese people could maintain for life a 4% reduction in weight at minimal financial cost, there would be a modest 1% reduction in heart attacks and strokes after 20 years. Rates of some microvascular complications [e.g., blindness, neuropathy, foot amputations] would also decline, but it would take at least 20 years—during which time weight loss was continuously maintained—for such an intervention to achieve cost-effectiveness.”
Dr. Kahn was the only author at the press briefing whose paper was not favorable to prevention. Several promoted a nationwide diabetes prevention program. “This would be a waste of resources,” said Dr. Kahn. “Instead we need a better understanding of the biological processes that cause so many people to put on weight. I don’t think we know enough about energy balance, specifically energy intake vs. energy expenditure. Our bodies regulate that very, very closely, and we just don’t know enough about the components of that [process], or why this imbalance occurs in some people and not others. We eat all the time, food is all around us, food is cheap and maybe our bodies can’t adapt to this environment.”
Until obesity researchers come up with answers, drug therapy is the way to go once diabetes develops, according to Dr. Kahn’s paper, “We can greatly reduce the likelihood of serious complications through early detection and proper medical management.” (Novo Nordisk, the company that makes diabetes drugs, was thanked by the editor of Health Affairs for partially funding this month’s issue.) However, Dr. Kahn expressed reservations about putting people on drug therapy when they are diagnosed with prediabetes, “The use of metformin or other glucose-lowering medications might help prevent diabetes, but initiating such therapy prior to the onset of diabetes is basically equivalent to diagnosing the disease at a lower glycemic [i.e., blood sugar level] threshold and therefore deserves more discussion.”
Additional information about prediabetes and exercise
More and more physicians have begun to treat prediabetes with drug therapy, though there is no evidence to show that this is safe or effective. One can see tacit support for this practice on the ADA website which states, “Before people develop type 2 diabetes, they almost always have prediabetes—blood glucose levels that are higher than normal but not yet high enough to be diagnosed as diabetes.” Read this about the pharmaceutical industry’s role in expanding the definition of diabetes 2 and why the current threshold for starting drug therapy is dangerously low for people with diabetes 2. click here And this about exercise, “You can be fat and fit.”
Maryann Napoli, Center for Medical Consumers©