Influence of the nutrition and health information presented on food labels on portion size consumed: a systematic review

Context: In recent decades, portion sizes have increased significantly. Although previous research indicates that food labels impact on product choice and healthiness perception, their impact on portion sizes consumed is less clear. Objective: This systematic review examined whether food label information influenced portion size consumption. Data sources: A search of 7 major electronic databases for studies published from 1980 to April 2016 was conducted. Data extraction: Two reviewers independently screened 11 128 abstracts. Data were extracted from 32 articles (comprising 36 studies). Results: Based on the test food used, the overall effects were found to be: no effect, a positive effect, or a negative effect. Labels displaying energy content (n=15 studies, 17 effects) and fat content information (n=13 studies, 14 effects) were evaluated most commonly, with exercise equivalent labels evaluated least (n=2 studies, 2 effects). Conclusions: Nutrition and health information presented on food labels has varying impacts on portion sizes consumed, from increased to decreased intake. Recommendations for future research include evaluating more recent food label types and achieving more consistent reporting standards.