Research

Adherence

Simple, high-contrast front-of-package warning labels (specifically black-and-white stop signs with 'High in' text) significantly improve consumer visualization, understanding, and intention to modify purchase behavior compared to complex or positive-framing labels.

For policymakers and public health advocates: Implement mandatory, high-contrast front-of-package warning labels (e.g., black-and-white stop signs with 'High in [Nutrient]'). Avoid complex traffic-light systems or positive-only labels, as evidence shows they are less understood and less effective at modifying purchase behavior, especially among low-SES populations. Simplicity and visual salience are key to driving healthier food choices.

GoodSupportsHIGH confidence
A simple black-&-white stop sign warning label was the best option to flag pre-packaged foods with an excess of energy or nutrients of concern for non-communicable diseases... the stop sign stating ‘Excess of <nutrient>’ had significantly better performance than the hand in terms of visualization, intention to purchase, and ability to modify intended purchase.
Marcela Reyes et al. · BMC Public Health · 2019

Why this rating

The study uses a robust mixed-methods approach (literature review, qualitative focus groups, expert review, and two quantitative sub-studies with large sample sizes n=600 and n=700) specifically designed to test the label's efficacy.

Source

Development of the Chilean front-of-package food warning label

Marcela Reyes et al. · BMC Public Health · 2019

cross_sectional · n=1300Cited 215×
Read the paper

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