Shahar Madjar, MD

The data about dieting is discouraging. The more weight we gain, the more weight we attempt to lose. But the two pandemics–one a pandemic of obesity, the other of weight-loss attempts–keep spreading and reach alarming proportions. The prevalence of obesity in the US is expected to reach nearly 50% by 2030; and at the same time, 42% of the general population report that they are trying to lose weight.

I have written here often about different types of diets. I told you about the challenges and the occasional, temporary success stories. It is one thing to lose weight; it is even harder to keep the weight off. Did I mention disappointment and discouraging results? It was therefore that I read with great interest a new study by Glenn A. Gaesser from Arizona State University and Siddhartha S. Angadi from the University of Virginia. The two researchers ask a provocative question: Should weight loss even be the primary focus of obesity treatment?

After extensive review of the literature, these researchers concluded that the answer is an astounding No! They propose another solution–instead of focusing on weight loss, patients and their doctors should focus their attention on physical activity and on fitness.

The information Gaesser and Angadi present relies on their extensive review of scientific research and on an analysis of several meta-analyses (a meta-analysis is a study that summarizes several other studies). Here are some of their impressions and findings:

The prevalence of both obesity and of weight-loss diets have increased in parallel over the past 40 years. This indicates that weight loss is not an effective strategy in the treatment of obesity. Instead of losing weight, individuals who attempt to lose weight often end up in a vicious, chronic weight-cycling: they lose weight but fail to reach their target weight, or fail to maintain their target weight; they then get frustrated, abandon the weight-loss attempts, and regain weight up to their original, or even higher weight. Chronic weight-cycling, nicknamed yo-yo diet, has been associated with health risks including higher all-cause mortality.

The researchers also maintain that while conventional wisdom holds that obesity is a risk factor for mortality, a closer examination reveals that the mortality risk associated with obesity is significantly reduced, or almost completely eliminated by high levels of physical activity. In other words, an overweight individual who is engaged in moderate or high level of physical activity has the same, or almost the same risk of mortality as that of a thinner individual.

The researchers found that the effect of physical activity on the risk factors for heart disease is at least equal and at times greater than the effect of weight loss on these same risk factors. This is true for blood pressure, serum glucose levels and HbA1c (the levels of sugars in the blood), and blood lipids such as cholesterol.

The researchers also report that weight loss isn’t consistently associated with decreased mortality. And that an increase in physical activity is associated with greater improvement in the mortality risk than weight loss.

Gaesser and Angadi conclude that doctors and their patients should shift their primary focus from weight loss to physical activity. In their final analysis, they bring about the results of two large studies. In the first study, the Finnish Diabetes Prevention Study, twice as many participants were able to adhere to their physical activity recommendation than to achieve their weight goal. This may indicate that an exercise program may be easier to follow than a weight-loss program. In the second study, the Nord-Trondelag Health Study which was performed on individuals with heart disease, adherence to high levels of physical activity was associated with 36% decrease in mortality while weight-loss was associated with 30% increase in mortality. This may indicate that physical activity may keep you alive while diet will not.

I asked myself, Can I eat my cake and have another too? According to Gaesser and Angandi, the answer might be, yes, you can eat as much as your heart desires as long as you run around the block for long enough. But how vigorous should my exercise be, and for how long should I engage in it? And, perhaps most importantly, is mortality risk the measure against which we should define success in the treatment of obesity?

I will examine these questions in my next article. Please stay tuned.

Editor’s note: Dr. Shahar Madjar is a urologist at Aspirus and the author of “Is Life Too Long? Essays about Life, Death and Other Trivial Matters.” Contact him at smadjar@yahoo.com.