Greater Healthful Dietary Variety Is Associated with Greater 2-Year Changes in Weight and Adiposity in the Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) Trial

Background: Greater healthful dietary variety has been inversely associated with body adiposity cross-sectionally; however, it remains unknown whether it can improve long-term weight loss. Objective: This study prospectively examined associations between healthful dietary variety and short-term (6 mo) and long-term (2 y) changes in adiposity in the Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) weight-loss trial completed in 2007. Methods: Healthful dietary variety was assessed from 24-h recalls with the use of the US Healthy Food Diversity index among participants aged 30-70 y with overweight/obesity (n = 367). Changes in the index between baseline and 6 mo were divided into tertiles representing reduced (T1), stable (T2), or increased variety (T3). Body weight and waist circumference (WC) were measured every 6 mo, and the percentage of body fat and trunk fat were measured at 6 mo and 2 y. Associations between changes in variety and short-term and long-term changes in adiposity were analyzed by use of multivariable-adjusted generalized linear models and repeated-measures ANOVA. Results: Regardless of dietary arm, T3 compared with T2 was associated with greater reduction in weight (-8.6 compared with -6.7 kg), WC (-9.1 compared with -6.1 cm), and body fat at 6 mo (beta = -4.61 kg, P < 0.05). At 2 y, individuals in T3 compared with those in T2 or T1 maintained greater weight loss[-4.0 (T3) compared with -1.8 kg (T2 and T1), P = 0.02] and WC reduction [-5.4 (T3) compared with -3.0 (T2) and -2.9 cm (T1), P = 0.01]. Total body fat and trunk fat reductions were similarly greater in T3 than in T2. Conclusions: Increasing healthful food variety in energy-restricted diets may improve sustained reductions in weight and adiposity among adults with overweight or obesity on weight-loss regimens. This trial is registered at clinicaltrials.gov as NCT00072995.