Arezoo Haghighian-Roudsari - ۱Department of Community Nutrition, National Nutrition and Food Technology Research Institute, School of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Nazli Namazi - ۲ Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
Pardis Irandoost - Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
Fatemeh Mohammadi Nasarabadi - Department of Food and Nutrition Policy and Planning Research, School of Nutrition and Food Sciences, National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mohammad Naemi Kermanshahi - Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
Maryam Mohammadi Nasarabadi - Department of Education and Promotion, Tehran University of Medical Sciences, School of Public Health, Tehran, Iran
Zahra Shahveghar - Department of Biochemistry and Dietetics, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
Mahdiyeh Khabbaz - Department of Community Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
Azizollaah Zargaraan - Department of Food and Nutrition Policy and Planning Research, School of Nutrition and Food Sciences, National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Ali Milani-Bonab - Department of Food and Nutrition Policy and Planning Research, School of Nutrition and Food Sciences, National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Samira Pourmoradian - Nutrition Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.

Background: Traffic Light Labeling (TLL) system is a simple tool to communicate information regarding the nutrients content of food products and has been widely applied to promote public health. However, evidence on the effectiveness of the TLL system on consumers’ choices is conflicting. The present study aims to systematically summarize the effects of TLL on consumers’ point of purchase behaviors. Methods: Five electronic databases, including PubMed/Medline, Scopus, Web of knowledge, the Cochrane library, and Science direct were searched from ۲۰۰۰/۰۱/۰۱ to ۲۰۲۱/۱۱/۰۱. Randomized-controlled trials, in English or Farsi languages, investigating the effects of TLL on choosing healthier foodstuffs or beverages were examined for eligibility and included in the review. Of ۶۴۰۸ potentially relevant publications (including ۱۲۵۵ duplicates), five clinical trials were finally included in the study. Results: The duration of the interventions ranged from ۴ to ۱۲ weeks and all studies except one had high methodological quality. Out of ۵, three clinical trials did not show positive effects of TLL on customers' choices to purchase healthier food products. Conclusions: The present review showed that TLL without other public health-promoting interventions may have no substantial effects on consumer’s food choice.  

Food Labeling, Consumer’s behavior, Choice behavior