The use of color-coded "traffic light" food labels and changes in the way popular items are displayed appear to have produced a long-term increase in the choice of more healthful food items among customers in a large hospital cafeteria. A Massachusetts General Hospital (MGH) team reports in the American Journal of Preventive Medicine that the previously reported changes in the proportions of more and less healthy foods purchased in the months after their program began have persisted up to two years after the labeling intervention was introduced.
"Our current results show that the significant changes in the purchase patterns of both hospital employees and all customers resulting from the labels and the choice architecture program did not fade away as cafeteria patrons became used to them," says Anne Thorndike, MD, MPH, of the MGH Division of General Medicine, who led the study. "This is good evidence that these changes in healthy choices persist over time."
Initiated in March of 2010, the program was developed by the research team - including leaders of the MGH Food and Nutrition Service - to deliver information about healthy food choices in a simplified way that did not require reading and understanding detailed food labels. The first phase involved the application of "traffic light" labels - green for the healthiest items, such as fruits, vegetables and lean sources of protein; yellow for less healthy items, and red for those with little or no nutritional value - to all items in the main hospital cafeteria. Several weeks before the labels were introduced, cafeteria cash registers began to identify and record each purchased item as red, yellow or green.
The second "choice architecture" phase, started three months after the labels were introduced, focused on cold beverages, pre-made sandwiches and chips - all of which were rearranged to display more healthful items where they were most likely to be selected. For example, bottled water, diet beverages and low-fat dairy products were positioned at eye level, while beverages with yellow or red labels were placed at lower levels.
