Minor lifestyle changes may not prevent weight gain more than monitoring alone

A recent investigation found that a slight decrease in caloric intake and increase in exercise over the course of two years did not prevent weight gain in overweight or obese people better than monitoring their weight alone.   

The study, published in the Canadian Medical Association Journal, was led by Robert Ross, PhD, professor of health kinesiology at Queen’s University. Ross and colleagues recruited 320 sedentary adults who were either overweight or obese. Participants were split in half. One group was asked to make minor lifestyle changes included a reduction of 100 calories per day and an extra 2,000 steps a day. The other group was asked only to monitor their weight over the course of two years. The study measured the weight, waist circumference, and cardiorespiratory fitness of participants after one year, two years, then again after three years. 

Of the 268 participants who completed the two-year study, the results showed no significant change in body weight between groups. Researchers found that after month three, six, 12, and 15 of the study, weight change between the monitoring and lifestyle change groups were significant, however, after 24 months the differences were no longer notable. In the follow-up period, of the 239 participants who returned, changes in weight between the groups remained insignificant. In addition, after 24 and 36 months, differences between participants’ waist circumference and cardiorespiratory fitness between groups were too small to draw any conclusions.

Although both methods did prevent weight gain, researchers determined that a small reduction in calories per day and a small increase in physical activity did not prevent weight gain any more than monitoring alone in obese and overweight people. As rates of obesity rise and contribute to chronic disease, this study offers new insights into the efficacy of different weight loss interventions.