Abstract

Background Front-of-package nutritional warning labels (WLs) are designed to facilitate identification and selection of healthier food choices. We assessed self-reported changes in purchasing different types of unhealthy foods due to WLs in Mexico and the association between the self-reported reductions in purchases of sugary beverages and intake of water and sugar-sweetened beverages.

Methods Data came from 14-17 year old youth (n=1,696) and adults ≥18 (n=7,775) who participated in the Mexican arm of the 2020-2021 International Food Policy Study, an annual repeat cross-sectional online survey. Participants self-reported whether the WLs had influenced them to purchase less of each of ten unhealthy food categories due to WLs. Among adults, a 23-item Beverage Frequency Questionnaire was used derive past 7-day intake of water and sugary beverages analyzed to determine the relationship between self-reported reductions in purchasing sugary drinks due to the WLs. Multilevel mixed-effects logistic regression models were fitted to estimate the percentage of participants who self-reported reducing purchases within each food group, and overall. Sociodemographic characteristics associated with this reduction were investigated as well.

Results Overall, 44.8% of adults and 38.7% of youth reported buying less of unhealthy food categories due to the implementation of WL, with the largest proportion reporting decreased purchases of cola, regular and diet soda. A greater impact of WLs on the reported purchase of unhealthy foods was observed among the following socio-demographic characteristics: females, individuals who self-identified as indigenous, those who were overweight, individuals with lower educational levels, those with higher nutrition knowledge, households with children, and those with a significant role in household food purchases. In addition, adults who reported higher water intake and lower consumption of sugary beverages were more likely to report reduced purchases of sugary drinks due to the WLs. Adults who reported greater water intake and lower sugary beverages intake were significantly more likely to report buying fewer sugary drinks due to the WLs.

Conclusion Our findings suggest that implementation of WLs has reduced purchases of unhealthy foods in Mexico. These results underscore the positive impact of the labeling policy particularly in subpopulations with lower levels of education and among indigenous adults.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

Funding for the International Food Policy Study (IFPS) was provided by a Canadian Institutes of Health Research (CIHR) Project Grant (PJT-162167), with additional support from the National Institute of Diabetes and Digestive and Kidney Disorders of the National Institutes of Health (R01 DK128967), the Public Health Agency of Canada (PHAC), and a CIHR-PHAC Applied Public Health Chair. Additional support for the IFPS Youth survey was provided by Health Canada. AC is supported by The National Council of Humanities, Sciences and Technologies of Mexico. JA is supported by the Medical Research Council (grant number MC_UU_00006/7). The content is solely the responsibility of the authors and does not necessarily represent the official views of the Canadian Institutes for Health Research, the National Institutes of Health or other sources of funding. The funding agencies had no role in the design of the study, the collection, analysis, or interpretation of data, or in the writing or decision to submit the manuscript for publication.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

University of Waterloo Research Ethics Committee, the Institutional Review Board at the University of South Carolina (only 2021 survey), and the Research Ethics Committee at the Instituto Nacional de Salud Publica in Mexico.

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Yes

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Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

AbbreviationsIFPSInternational Food Policy StudyWLswarning labelsFoPLfront of package nutrition labelBMIbody mass index