Researchers in China tested different types of warning labels on sugary products to see which ones actually stop people from buying them. They studied 1,800 shoppers and found that simple warning labels (like a red stop sign) were most effective at making people avoid high-sugar items. Other label styles worked too, but in different ways. Interestingly, some labels backfired by making people feel the product was healthier than it actually was. The study shows that how we design these labels really matters for helping people make better food choices.
The Quick Take
- What they studied: Which types of front-of-package labels (the labels on the front of food boxes) are best at stopping people from buying sugary products
- Who participated: 1,800 shoppers across China who participated in realistic shopping experiments where they made actual food choices
- Key finding: Warning labels (like a red alert symbol) were significantly more effective than traditional nutrition facts at reducing purchases of high-sugar products. Warning labels worked best, followed by traffic light labels, then health tick labels. One type of label actually made people more likely to buy sugary products.
- What it means for you: If you see a warning label on a sugary product, it’s a strong signal to reconsider that purchase. However, be aware that some labels might make unhealthy products seem healthier than they really are. This research suggests governments should use warning-style labels to help people make better choices.
The Research Details
Researchers conducted randomized controlled experiments, which is like a fair test where some people see one type of label while others see different labels. They used 1,800 consumers across China and had them make real food choices in experimental settings. This approach is powerful because it lets researchers see exactly how different labels change what people actually buy, not just what they say they would buy.
The study tested five different label types: the traditional Nutrition Facts Panel (the detailed label most products have), a Warning Label (a simple alert-style label), a Traffic Light Label (using red, yellow, and green colors like traffic signals), a Health Tick Label (a simple checkmark or approval symbol), and a Positive Attribute label (highlighting good things about the product). By comparing how people responded to each label type, researchers could figure out which ones worked best and why.
This research approach is important because it goes beyond just asking people what they think—it actually measures what they do. Real behavior is more important than opinions. The study also looked at the ‘why’ behind the results, examining how labels affect people’s thoughts and feelings about sugar, which helps explain the mechanisms. This deeper understanding helps policymakers design labels that will actually work in real life.
This is a well-designed study using randomized controlled experiments, which is considered a strong research method. The large sample size of 1,800 participants across an entire country makes the results more reliable. However, the study was conducted in China, so results might differ in other countries with different cultures and shopping habits. The experimental setting, while controlled, may not perfectly match real-world grocery shopping where people are rushed or distracted.
What the Results Show
The Warning Label was the clear winner. Compared to the standard Nutrition Facts Panel, the Warning Label reduced how much money people were willing to spend on high-sugar products—and this effect was the strongest of all label types tested. The Traffic Light Label (using red, yellow, and green colors) also significantly reduced purchases of sugary items, though not as powerfully as the Warning Label.
The Health Tick Label (a simple approval symbol) also reduced purchases of high-sugar products, but less effectively than the Warning Label or Traffic Light Label. Surprisingly, the Positive Attribute Label (which highlighted good things about the product) actually had the opposite effect—it made people more willing to buy high-sugar products compared to the standard label.
The research revealed why these differences happened. Warning Labels and Traffic Light Labels worked by making people more concerned about sugar content, which then triggered worry about health risks and a desire to avoid the product. The Health Tick Label worked differently—people liked its simplicity and attractiveness, but it also created a ‘health halo effect,’ meaning people thought the product was healthier overall than it really was, which weakened its effectiveness.
An important discovery was the ‘health halo effect’ caused by the Health Tick Label. Even though this label reduced purchases of high-sugar products, it did so less effectively because it made people feel the product was generally healthy, which conflicted with the warning about sugar. The Positive Attribute Label backfired because it reduced people’s concern about sugar and made the label seem too simple, actually encouraging purchases of high-sugar items. The study also found that ‘sugar concern’—how worried people are about sugar—was the key factor that determined whether labels would work.
This research builds on previous studies about nutrition labels by showing that not all labels work the same way. Earlier research suggested that any clear label was better than nothing, but this study reveals that the design and style of the label matters enormously. The finding that warning-style labels are most effective aligns with research from other countries, suggesting this approach could work globally. However, the discovery of the health halo effect adds new understanding about why some seemingly helpful labels can backfire.
The study was conducted in China, so the results might not apply exactly the same way in other countries with different cultures, education levels, or shopping behaviors. The experiments were done in controlled settings rather than real grocery stores, which might not perfectly reflect how people actually shop when they’re in a hurry or distracted. The study focused on willingness to pay in experiments rather than actual long-term purchasing behavior, so we don’t know if these effects would last over weeks or months. Additionally, the study only looked at high-sugar products, so results might differ for other types of unhealthy foods.
The Bottom Line
If you’re trying to reduce sugar intake, look for products with warning-style labels or traffic light labels—these are strong signals that the product is high in sugar and worth reconsidering. Be cautious of products with simple approval symbols or positive attribute labels, as these might make unhealthy products seem better than they are. For policymakers, the evidence strongly suggests (with high confidence) that warning-style labels are the most effective tool for reducing purchases of high-sugar products. Medium confidence: Traffic Light Labels also work well and might be more acceptable to food companies. Lower confidence: Health Tick Labels have mixed results and can create misleading impressions.
This research matters most for people trying to reduce their sugar intake, parents making food choices for their families, and government officials designing nutrition policies. It’s especially relevant in countries like China and other emerging markets where sugary product consumption is rising. Food companies should pay attention because these findings show what label designs will actually influence consumer behavior. People with diabetes or prediabetes should find this particularly useful. However, this research is less directly applicable to people who already carefully read detailed nutrition information or those in countries that already have strong warning label systems in place.
Based on this research, the effects of labels appear to happen relatively quickly—during the shopping decision itself. You might notice changes in your purchasing habits within a few shopping trips if you start paying attention to warning labels. However, long-term behavior change (sticking with lower-sugar choices for months) would require consistent attention to these labels and probably other supporting strategies like habit formation and gradual taste adjustment.
Want to Apply This Research?
- Track the number of high-sugar products you purchase per week and note which label types appeared on those products. Set a goal to reduce high-sugar purchases by 20% over four weeks, specifically by choosing products with warning or traffic light labels instead.
- When shopping, use the app to scan product barcodes and see a label-style warning if the product is high in sugar. Create a shopping list that filters for products with warning-style or traffic light labels. Set reminders to check labels before adding sugary items to your cart.
- Weekly tracking of sugar intake from packaged foods, with a focus on the types of labels on products you purchase. Monthly reviews of your label awareness—how often you actually notice and consider label types when making choices. Track any changes in energy levels, weight, or how you feel after reducing high-sugar product purchases.
This research provides evidence about how different label designs affect purchasing decisions, but it does not constitute medical advice. Individual responses to labels may vary based on personal factors, education level, and cultural background. If you have specific health concerns related to sugar intake, diabetes, or other conditions, please consult with a healthcare provider or registered dietitian. This study was conducted in China and may not apply identically in all countries or populations. The findings reflect experimental conditions and may differ from real-world grocery shopping behavior. Always read complete nutrition information on products, not just front-of-package labels, to make fully informed food choices.