Robert Ross

Summary We sought to determine whether small changes in physical activity and diet could prevent adverse changes in body composition over 2 years in adults with overweight and obesity. Previously inactive adults ( N = 289) were included in a secondary analysis of data derived from a 3‐year, single‐centre, two‐arm, longitudinal randomized controlled trial. Participants were randomized to a small change approach ( N = 144, body mass index: 32.4 ± 4.2 [mean ± standard deviation], age: 52.3 ±. 10.6 years) or usual care ( N = 145, body mass index: 32.4 ± 4.2, age: 53.1 ± 10.6 years). Small change approach participants were counselled to make small changes in diet and physical activity, while usual care participants were asked to maintain their usual lifestyle. Adiposity, lean mass and bone mineral density were measured by dual‐x‐ray absorptiometry. The change in total adiposity was significantly greater in the small change approach group than usual care at 6 and 12 months but did not remain significant at 24 months (mean change [standard error] −0.8 [0.4] vs. −0.7 [0.4] kg; difference 0.6, 95% confidence interval [CI] −1.2 to 1.1). Changes in visceral fat were significantly greater in the small change approach than usual care at 6 and 12 months but did not remain significant at 24 months (−0.04 [0.03] vs. 0.02 [0.03] kg; difference 0.06, 95% CI: −1.5 to 0.3). Changes in lean mass or bone mineral density were not significantly different between groups at any time point (all p > 0.1). The small change approach did not prevent gains in adiposity or losses in lean mass compared to usual care at 2 years in adults with overweight or obesity. No difference from baseline in adiposity, lean mass or bone mineral density was observed in either arm of the trial.