Short-Term Weight Loss with Diet and Physical Activity in Young Adults: the IDEA Study

BACKGROUND: Few studies have examined the effect of a behavioral weight loss intervention (BWLI) on young adults (age = 18 to 35 years). METHODS: Participants (N=470) enrolled in a 6 month BWLI that included weekly group sessions, a prescribed energy restricted diet and moderate-to-vigorous physical activity (MVPA). Assessments included weight, body composition, fitness, lipids, glucose, insulin, resting blood pressure and heart rate, physical activity, and dietary intake. Data are presented as median [25(th), 75(th) percentiles]. RESULTS: Retention was 90% (N=424; age: 30.9 [27.8, 33.7] years; BMI: 31.2 [28.4, 34.3] kg/m(2)). Participants completed 87.5% (76.1%, 95.5%) of scheduled intervention contacts. Weight and body fat decreased while fitness increased (p<0.0001). MVPA in bouts ≥10 minutes increased (p<0.0001), though total MVPA did not change significantly. Sedentary time decreased (p=0.03). Energy and percent fat intake decreased, while percent carbohydrate and protein intake increased (p<0.0001). Systolic and diastolic blood pressure, total cholesterol, LDL cholesterol, triglycerides, glucose, and insulin decreased (p<0.0001). CONCLUSIONS: A 6 month BWLI produced favorable changes in dietary intake and physical activity and elicited favorable changes in weight and other health outcomes in young adults. MVPA performed in bouts of ≥10 minutes was associated with greater weight loss, but sedentary behavior was not.