Objectives: The increase in consumption of sugar‐added beverages over recent decades may be partly responsible for the obesity epidemic among U.S. adolescents. Our aim was to evaluate the relationship between BMI changes and intakes of sugar‐added beverages, milk, fruit juices, and diet soda.

Research Methods and Procedures: Our prospective cohort study included >10, 000 boys and girls participating in the U.S. Growing Up Today Study. The participants were 9 to 14 years old in 1996 and completed questionnaires in 1996, 1997, and 1998. We analyzed change in BMI (kilograms per meter squared) over two 1‐year periods among children who completed annual food frequency questionnaires assessing typical past year intakes. We studied beverage intakes during the year corresponding to each BMI change, and in separate models, we studied 1‐year changes in beverage intakes, adjusting for prior year intakes. Models included all beverages simultaneously; further models adjusted for total energy intake.

Results: Consumption of sugar‐added beverages was associated with small BMI gains during the corresponding year (boys: +0.03 kg/m² per daily serving, p = 0.04; girls: +0.02 kg/m², p = 0.096). In models not assuming a linear dose‐response trend, girls who drank 1 serving/d of sugar‐added beverages gained more weight (+0.068, p = 0.02) than girls drinking none, as did girls drinking 2 servings/d (+0.09, p = 0.06) or 3+ servings/d (+0.08, p = 0.06). Analyses of year‐to‐year change in beverage intakes provided generally similar findings; boys who increased consumption of sugar‐added beverages from the prior year experienced weight gain (+0.04 kg/m² per additional daily serving, p = 0.01). Children who increased intakes by 2 or more servings/d from the prior year gained weight (boys: +0.14, p = 0.01; girls +0.10, p = 0.046). Further adjusting our models for total energy intake substantially reduced the estimated effects, which were no longer significant.

Discussion: Consumption of sugar‐added beverages may contribute to weight gain among adolescents, probably due to their contribution to total energy intake, because adjustment for calories greatly attenuated the estimated associations.