During the nutrition transition in Chile, dietary changes were marked by increased consumption of high-energy, nutrient-poor products, including sugar-sweetened beverages (SSBs). Obesity is now the primary nutritional problem in posttransitional Chile. We conducted a randomized controlled trial to examine the effects on body composition of delivering milk beverages to the homes of overweight and obese children to displace SSBs. We randomly assigned 98 children aged 8-10 y who regularly consumed SSBs to intervention and control groups. During a 16-wk intervention, children were instructed to drink 3 servings/d (approximately 200 g per serving) of the milk delivered to their homes and to not consume SSBs. Body composition was measured by dual-energy X-ray absorptiometry. Data were analyzed by multiple regression analysis according to the intention-to-treat principle. For the intervention group, milk consumption increased by a mean (+/- SEM) of 452.5 +/- 37.7 g/d (P < 0.0001), and consumption of SSBs decreased by -711.0 +/- 33.7 g/d (P < 0.0001). For the control group, milk consumption did not change, and consumption of SSBs increased by 71.9 +/- 33.6 g/d (P = 0.04). Changes in percentage body fat, the primary endpoint, did not differ between groups. Nevertheless, the mean (+/- SE) accretion of lean body mass was greater (P = 0.04) in the intervention (0.92 +/- 0.10 kg) than in the control (0.62 +/- 0.11 kg) group. The increase in height was also greater (P = 0.01) in the intervention group (2.50 +/- 0.21 cm) than in the control group (1.77 +/- 0.20 cm) for boys but not for girls. Replacing habitual consumption of SSBs with milk may have beneficial effects on lean body mass and growth in children, despite no changes in percentage body fat. This trial was registered at clinicaltrials.gov as NCT00149695.
