Effect of different front-of-package food labels on identification of unhealthy products and intention to purchase the products- A randomised controlled trial in South Africa

Makoma Bopape; Jeroen De Man; Lindsey Smith Taillie; Shu Wen Ng; Nandita Murukutla; Rina Swart

doi:10.1016/j.appet.2022.106283

Effect of different front-of-package food labels on identification of unhealthy products and intention to purchase the products- A randomised controlled trial in South Africa

Appetite. 2022 Dec 1:179:106283. doi: 10.1016/j.appet.2022.106283. Epub 2022 Aug 24.

Authors

Makoma Bopape¹, Jeroen De Man², Lindsey Smith Taillie³, Shu Wen Ng⁴, Nandita Murukutla⁵, Rina Swart⁶

Affiliations

¹ Department of Human Nutrition and Dietetics, Faculty of Health Sciences, University of Limpopo, South Africa; Faculty of Community and Health Sciences, School of Public Health, University of the Western Cape, South Africa. Electronic address: makoma.bopape@ul.ac.za.
² Department of Family Medicine and Population Health, University of Antwerp, Antwerp, Belgium. Electronic address: Jeroen.DeMan@uantwerpen.be.
³ Carolina Population Center and Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, USA. Electronic address: taillie@unc.edu.
⁴ Carolina Population Center and Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, USA. Electronic address: shuwen@unc.edu.
⁵ Vital Strategies, New York City, New York, USA. Electronic address: NMurukutla@vitalstrategies.org.
⁶ Department of Dietetics and Nutrition, Faculty of Community and Health Sciences, University of the Western Cape, South Africa. Electronic address: rswart@uwc.ac.za.

PMID: 36027994
DOI: 10.1016/j.appet.2022.106283

Abstract

This study aimed to evaluate the effect of different labels on participants identifying products high in nutrients of concern; identifying unhealthy products, and intention to purchase unhealthy products. This blinded randomised controlled trial included a representative sample of South African households (n = 1951). Per household we selected a member primarily responsible for food purchases. Participants were randomised into the Warning Label (WL), Guideline Dietary Amounts (GDA) or Multiple Traffic Light (MTL) arms. Each participant answered questions in a no label condition (control) followed by same questions in the label condition (experiment). Complete data were collected and analysed for 1948 participants (WL = 33.7%, GDA = 32.1% and MTL = 34.2%). The probability of correctly identifying products high in nutrients of concern and identifying products as being unhealthy was higher with the WL compared to the GDA or MTL for most items. There was no difference in performance between the GDA and the MTL when considering all items together. A higher percentage of participants reported a lower intention to purchase an unhealthy product after exposure to the WL compared to MTL for 5 out of 6 products; 2 out of 6 products for the WL compared to GDA and 2 out of 6 products for GDA compared to MTL. Compared to the control condition, exposure to each of the labels resulted in better identification of nutrients of concern, unhealthy products and a lower intention to purchase when considering all specific outcome items together. The WL showed a higher potential to enable South African consumers to identify products high in nutrients of concern, identify unhealthy products and discourage purchasing of unhealthy products.

Keywords: Front-of-package food labels; Noncommunicable diseases; Obesity; Purchasing intention; Unhealthy products.

Publication types

Randomized Controlled Trial
Research Support, Non-U.S. Gov't

MeSH terms

Choice Behavior
Consumer Behavior
Food Labeling* / methods
Food Preferences
Health Knowledge, Attitudes, Practice
Humans
Intention*
Nutritive Value
South Africa