Effect of front-of-package nutrition labeling on food purchases: a systematic review

Objectives: This study systematically reviewed evidence from interventions on the effect of front-of-package (FOP) nutrition labeling on food purchases. Study design: The study design used in this study is a systematic review. Methods: Keyword search was performed in PubMed, Web of Science, Scopus, and Cochrane Library. Results: Fifteen studies (10 randomized controlled trials, four pre-post studies, and one case-control study) met the eligibility criteria and were included in the review. Five studies were conducted in a controlled setting through the establishment of an online virtual supermarket or physical laboratory food store solely for the intervention. In contrast, the remaining ten studies were conducted in a naturalistic setting where people commonly purchase foods (e.g., supermarket, grocery store, school/hospital cafeteria, or vending machine). FOP labels assessed included traffic lights, health star rating, daily intake guides, health warnings, and high sugar symbol labels. Compared with the control, FOP labels were effective for helping participants make healthier food purchase decisions in five of the 12 studies that assessed traffic lights labels, in one of the two studies that assessed health warning labels, and in one study that assessed high sugar symbol labels. Three assessed health star ratings and one assessed daily intake guide labels, but none revealed an effect on food purchases compared with the control. Conclusions: Findings on the effectiveness of FOP nutrition labels in ‘nudging’ consumers toward healthier food purchases remain mixed and inconclusive. Future studies should examine other types of FOP labels beside the traffic lights labels and explore the different effects by consumer affordability, population subgroup, and shopping environment.