Nutri-Score and warning labels represent two widely implemented Front-of-Pack Nutrition Labelling (FOPNL) systems aimed at promoting healthier consumer choices and addressing the global burden of diet-related non-communicable diseases (NCDs). Despite their growing adoption, comparative evidence regarding their effectiveness — particularly in low- and middle-income countries (LMICs) — remains limited.
The study by König et al. (2025), ‘Nutri-Score and nutrition warning labels are effective in guiding hypothetical choice in Indonesia, Mexico, and Türkiye: Results from a cross-country online experiment’, seeks to fill this knowledge gap by assessing the impact of these labeling systems on purchasing intentions and nutrient perception across three upper-middle-income countries. (1)
Nutrition transition and FOPNL: study context and objectives
Indonesia, Mexico and Türkiye are all upper-middle-income countries, with a combined population of 485 million. Over the past decades, all three countries have all undergone the nutrition transition toward Western diets high in ultra-processed foods and whose populations are today characterized by high levels of obesity and diet-related Non-Communicable Diseases (NCDs); public health action is thus urgently needed. (2)
The researchers from the Universities of Wien (Austria) and Bayreuth (Germany) aimed to investigate the effectiveness of front-of-pack nutrition labeling (FOPNL) systems through two main objectives:
- assess the impact of two major FOPNL systems — Nutri-Score and warning labels — on consumer purchasing intentions and perceived healthiness of food products;
- evaluate how these FOPNL systems influence the nutritional quality of selected products, specifically regarding calorie, sugar, sodium, and saturated fat content, in a cross-country online study.
The authors expected that these labels would mainly affect consumer evaluations of nutritional attributes directly referenced by the labeling format. Specifically:
- Nutri-Score as a summary evaluation of the product’s healthiness should be most effective in guiding the identification of healthy products, while
- warning labels informing about high contents of calories, sugar, saturated fats, and sodium should be most effective in guiding the identification of unhealthy foods.
In addition, König et al. (2025) explored the impact of familiarity with a labelling system by comparing study participants from Mexico, where warning labels are mandatory since 2020, to study participants from Indonesia and Türkiye, where no FOPNL system is currently used.
Study design and methodology
Participants and procedure
The study included 639 participants, recruited via social media: 212 from Indonesia, 203 from Mexico, and 224 from Türkiye. To explore how different front-of-pack labels influence consumer choices, the researchers conducted a three-condition, between-subjects online experiment. Participants were randomly assigned to one of three groups, each exposed to a different labeling condition:
- Nutri-Score group: saw products with the color-coded A-E nutrition grade;
- warning label group: saw products with “high in” warnings for critical nutrients;
- control group: saw products with no front-of-pack labels.
Stimuli development
The researchers selected eight food categories (chips, instant noodles, processed meats, condiments, sweet spreads, cookies, yoghurt, and fruit drinks) based on their local popularity and nutritional variability across Indonesia, Mexico, and Türkiye.
To ensure ecological validity, products were chosen to mirror real-market options, with pairs matched for brand familiarity and packaging design (e.g., Doritos vs. Patos chips in Türkiye).
Nutritional profiles were standardized: Nutri-Scores were calculated using the 2015 algorithm, while warning labels followed Mexico’s ‘high in’ criteria (e.g., black octagons for excess sugar/sodium). For consistency, Mexican products’ existing warnings were digitally removed and replaced with experimental labels.
Experimental procedure
Participants began with a brief tutorial explaining both label systems (to control for prior knowledge gaps). They then viewed randomized product pairs from the eight categories, answering for each:
- purchase intent (‘Which would you buy, or neither?’);
- healthiness perception;
- nutrient comparisons (e.g., ‘Which has more sugar?’).
The task was hosted on Tivian Unipark, with labels displayed beneath product images. Post-task, participants rated label acceptability (e.g., ‘I trust this label’ on a 6-point scale). To mitigate bias, the control group saw identical products without labels.
Key Findings: Nutri-Score outperforms warning labels
The research revealed clear differences in how Nutri-Score and warning labels influence food choices. The Nutri-Score proved more effective overall, helping consumers pick healthier options in five out of eight food categories tested, including items like chips, meats, and yogurt. In comparison, warning labels only significantly impacted choices for one category (processed meats).
When it came to understanding nutritional content, the Nutri-Score helped shoppers better identify products high in calories, sugar, and sodium across most food types. Warning labels worked moderately well for spotting saturated fat but were less consistent for other nutrients.
Interestingly, both labeling systems worked similarly well across all three countries – even in Mexico where warning labels are already mandatory. This suggests people can understand and use these labels without prior exposure, with the Nutri-Score’s color-coded system being particularly intuitive.
Conclusions
The study concludes that while both FOPNL systems can guide consumers toward healthier choices, Nutri-Score tends to produce larger and more consistent effects for promoting overall healthier choices, while warning labels could still be useful for targeting specific nutrients. However, the findings also highlight that labels alone aren’t enough – consumer education remains essential for maximum impact.
Dario Dongo
References
(1) König, L. M., Akad, E., Gunawan, G., Rocha Gonzales, D. V., & Dorlach, T. (2025). Nutri-Score and nutrition warning labels are effective in guiding hypothetical choice in Indonesia, Mexico, and Türkiye: Results from a cross-country online experiment. Frontiers in Public Nutrition Labelling. https://tinyurl.com/ztezdr7m
(2) World Obesity Federation. World Obesity Atlas 2024. London: World Obesity Federation; 2024.
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
