Thirty years ago Leonard Epstein, PhD, Head of Behavioral Medicine at University of Buffalo developed a food categorization system to help children lose weight based on green for “go,” yellow for “slow”and red for “whoa.”

His system combined data on nutrients and calories and was easy to understand. After all, he was designing for children and their families.  Green light foods are those that are low in sugar, low in fat, low in calorie density and have high nutritional value.  These include most fruits and vegetables. Kids were encouraged to eat these foods freely. Yellow light foods are nutrient-rich, moderate-calorie food–whole grain pasta, rice, and bread as well as lean proteins. With yellow light foods healthy portion control is still key. Finally, red light foods are foods that have little nutritional value and are high in sugar, fat and calories. They should be eaten sparingly and considered a “treat.”  Dr. Epstein’s approach was broadly praised and Stanford’s Center for Healthy Weight, among others, adapted the system for its highly successful family-based program.

What’s interesting is that in recent years, faced with the failure of traditional weight loss approaches, many have started to look to the Traffic Light system to help adults with weight management. In 2010, a team of researchers led by Anne Thorndike, MD, MPH,  from Massachusetts General Hospital conducted a study on the effects of food labeling on food choice. The goal was to provide information about healthy food choices in a simplified manner, one that did not require reading or understanding detailed food labels, and observe purchasing behavior. Using the Traffic Light System, the researchers applied color-coded labels to food in the hospital cafeteria.  The results were exactly what they had hoped for. After two years, overall purchases of green items had increased by 12 percent and red items decreased by 20 percent. In addition, sales of sugary red-light sodas dropped by 39 percent while green light beverages increased 10 percent.  

Adults, like kids, prefer and benefit from simpler solutions. In Thorndike’s study one woman noted that at first she thought the system was simple-minded and patronizing. But increasingly, she found herself considering the “color” of her cravings every time she ordered food.

In another study conducted at the health company Humana, researchers looked at the impact of numeric calorie vs Traffic Light color coding labels on online food purchases.  They found that both types of labels reduced calories by 10%. Traffic light labels achieved the same reduction in calories even in the absence of numeric information, suggesting that consumers benefit from data that identifies healthier choices but rely little on the calorie information.   Other studies have shown that calorie counting involves higher cognitive load and can even lead to increased food decision-making stress.

Having seen this data, pioneering companies are adopting the Traffic Light System in their corporate cafeterias both to promote healthier choices and to reduce stress. Google, for example, uses traffic light food labeling not only in its cafeteria, but for snack items as well. When National Public Radio moved into its new headquarters in 2013, its cafeteria menu included red, yellow, and green dots next to items. Even the Army has a Go for Green initiative that uses the traffic light method at dining facilities.

Outside the US, the shift from calories to color coding has been even more rapid.  A government study in the UK showed that traffic light labeling in combination with standard information about calories, protein , sugar, fat and salt is significantly easier to understand than using text-based information alone.  Today, the Departments of Health in both the UK and Australia have introduced voluntary traffic light food labeling schemes in their supermarkets to simplify healthy food selection.

For its part, Kurbo has licensed the Stanford Traffic Light program, adapted it into a mobile app and virtual coaching program which is used all over the world by kids and adults to develop healthier eating and exercise habits.  Lindsay Lagreid, a young professional woman who recently lost 20 lbs with help from the Kurbo app and coaching program, said she had struggled with weight all her life “and had tried every diet under the sun.”  

“Before, I would avoid tracking my unhealthy meals,” she says.  “But I’ve never felt that way with Kurbo because I know that I can have those red light foods. In addition, though the app was initially designed for kids, I was able to work through issues that adults face with weight loss, like going out to drinks with friends, without ever feeling judged by my coach.”

To learn more about this exciting new design for weight management programs, please attend our webinar May 11th, 1 pm EST with presenters Kurbo Co-founder Thea Runyan, who has spent 15 years with the Stanford Center for Healthy Weight,  and Massachusetts General cafeteria study author Anne Thorndike, MD, MPH.

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¹ Thorndike, A. N., Riis, J., Sonnenberg, L. M., & Levy, D. E. (2014). Traffic-light labels and choice architecture: promoting healthy food choices. American journal of preventive medicine, 46(2), 143-149.

² http://www.massgeneral.org/News/pressrelease.aspx?id=1660

³ http://civileats.com/2015/01/07/stop-n-go-can-traffic-light-labels-help-us-eat-better/

https://www.foodwatch.org/en/what-we-do/topics/traffic-light-labels/more-information/research-supports-traffic-light-colours/