RESUMO
Obesity is a challenging public health problem that affects millions of Americans. Increasingly policy makers are seeking environmental and policy-based solutions to combat and prevent its serious health effects. Calorie labeling mandates, including the provision in the 2010 Patient Protection and Affordable Care Act that is set to begin in 2014, have been one of the most popular and most studied approaches. This review examines 31 studies published from January 1, 2007 through July 19, 2013. It builds on Harnack and French's 2008 review and assesses the evidence on the effectiveness of calorie labeling at the point of purchase. We find that, while there are some positive results reported from studies examining the effects of calorie labeling, overall the best designed studies (real world studies, with a comparison group) show that calorie labels do not have the desired effect in reducing total calories ordered at the population level. Moving forward, researchers should consider novel, more effective ways of presenting nutrition information, while keeping a focus on particular subgroups that may be differentially affected by nutrition policies.