Lifestyle Modification for Obesity New Developments in Diet, Physical Activity, and Behavior Therapy

Expert panels sponsored by both the World Health Organization and the National Institutes of Health have recommended that obese adults (ie, body mass index ≥30 kg/m2), as well as those who are overweight (body mass index of 25–29.9 kg/m2) and have comorbid conditions, lose 10% of their initial weight.1,2 A comprehensive program of lifestyle modification is considered the first option for achieving this goal.2 Lifestyle modification, also referred to as behavioral weight control, includes 3 primary components: diet, exercise, and behavior therapy.3 This narrative review examines weight losses achieved with this approach, as well as new developments with each of the 3 components. Comprehensive lifestyle modification programs typically provide weekly individual or group treatment sessions designed to modify eating and activity habits.4 This approach is exemplified by the Diabetes Prevention Program (DPP),5 which randomly assigned >3200 participants with impaired glucose tolerance to 1 of 3 groups: placebo, metformin, or lifestyle modification. Participants in the lifestyle intervention were provided 16 individual counseling sessions during the first 24 weeks and at least every-other-month sessions thereafter. They were prescribed a reduced calorie, low-fat diet of conventional foods (1200–2000 kcal/d, depending on body weight) and 150 min/wk of physical activity (typically brisk walking), with the goal of losing 7% of initial weight.5,6 After an average of 2.8 years, participants in the lifestyle intervention lost 5.6 kg in comparison with losses of 2.1 kg and 0.1 kg in the metformin and placebo groups, respectively. The risk in the lifestyle group of developing type 2 diabetes was reduced by 58% in comparison with placebo and by 31% in comparison with metformin.5 Ten years after randomization, lifestyle-treated participants had regained nearly to their baseline weight (with no significant differences in weight loss among groups). …