Choosing meals that are healthy and environmentally friendly can be a confusing and difficult task for most of us. But it's a lot clearer — and easier — if you have a traffic light-type system — red, green or yellow — to guide the way, a new study shows.
Researchers at Queen Mary University of London used traffic light labels in a situation designed to simulate lunch meals at a cafeteria. Red, amber and green labels designated how healthy and how environmentally friendly the meal options were.
People in the study saw pictures of meals they could choose for lunch. The meals ranged from more to less healthy and from more to less environmentally friendly. Participants' meal choices without traffic light labels were recorded and then compared to meal choices when there were present.
While it might sound like a case of information overload, seeing both green light labels, as compared to just one, increased the positive effect on people’s food choices.
This type of behavioral intervention serves as a prompt or nudge and is designed to improve the decisions people make in their everyday lives.
Other studies have looked at traffic light label systems and their impact on people’s food choices, but this study measured their use in a simulated, everyday lunch setting, much like the circumstances where people actually make their food choices.
“[U]sing traffic light labels on menus influences the meals people choose, and so this simple technique could easily be implemented on menus in bars, cafes, restaurants as well as canteens, to indicate to people the greenness as well as the healthiness of food items,” lead author of the study, Magda Osman, of Queen Mary University of London, said in a statement.
The persuasive effects of traffic light labels are boosted when people receive general information about daily calorie intake and acceptable levels of carbon emissions associated with their meal choices, Osman added.
The study is published in Appetite.