Research issues: the food environment and obesity

"Research Issues: The Food Environment and Obesity" is an article series commissioned by the American Society for Nutrition and The Obesity Society in an attempt to consider the state of understanding on this topic and identify key knowledge gaps. Roberts and Karl focus on the role of energy density in the regulation of energy intake and body weight and offer recommendations for prioritizing research: Finkelstein et al examine food and beverage purchases as a function of price changes and conclude that targeted food taxes and subsidies alone are unlikely to substantially affect obesity. Pereira points out the difficulty in establishing the strength of the association between intake of sugar-sweetened beverages and weight gain and obesity. Johnson and Wardle review the effects of palatability and variety on eating behavior and weight. Livingstone and Pourshahidi examine the impact of portion size manipulations on energy intake and weight management and find that consumers generally tend to eat proportionally more as portion size increases. Kant focuses on the efficacy and effectiveness of eating frequency manipulation for body weight management and finds that such manipulation has consistently yielded null results. Finally, Gordon-Larsen identifies several limitations of the existing literature regarding neighborhood access to healthy foods.