Beverages and body weight: challenges in the evidence-based review process of the Carbohydrate Subcommittee from the 2010 Dietary Guidelines Advisory Committee

Concern about the role of beverages, especially those containing sugar, in the obesity epidemic continues to escalate. Bans on sugar-sweetened beverages and chocolate milk have expanded from the school cafeteria to the ballpark and convenience store. This review describes the experience of the 2010 Dietary Guidelines Advisory Committee (DGAC) in conducting an evidence-based review of dietary exposure and health outcomes. The following four topics relevant to fluids and body weight were reviewed: added sugar, noncaloric sweeteners, food form and body weight, and macronutrients and satiety. There were limited and conflicting data on how liquids and solids affect energy intake and body weight. Fluid intake is typically not tracked in prospective, cohort longitudinal studies; thus, data are not available on fluid intake and health status from studies using the strongest epidemiologic designs. Despite public perception that beverages are linked to increased body weight compared with whole foods, evidence-based reviews of this topic do not support that liquid calories are processed differently in the body. The practical recommendation to replace caloric beverages with water as an aid to control weight is based on calorie reduction, rather than a link between added-sugar intake and obesity.