Sugars-containing beverages and post-prandial satiety and food intake

Reports from food disappearance and food intake surveys, and from prospective and intervention studies appear to support a contributing role for sugars-sweetened beverages in obesity. Often these studies are interpreted to imply that there is a direct causal link between sugars consumption, especially from beverages, and obesity. The purpose of this review is to determine if the associations reported between sugars consumption and obesity are biologically plausible. The evaluation of biologic plausibility is examined by answering the following five questions: (1) Do sugars and sugars in solutions bypass food intake regulatory systems? (2) Do sugars and sugars in solutions suppress food intake? (3) Do sugars sweetened, commercially available beverages (e.g. soft drinks) suppress food intake? (4) Do sugars in solid form stimulate intake regulatory systems and suppress food intake more than those in beverages? and (5) Do energy-containing beverages contribute to energy imbalances because regulatory systems for hunger and thirst interact? It is concluded that the associations between sugars-sweetened beverages and obesity must be viewed as circumstantial because biological plausibility, based on known physiologic mechanisms regulating food intake and energy balance, and short-term experimental studies, does not support cause and effect conclusions.