Traffic-light labels and choice architecture: promoting healthy food choices

Preventing obesity requires maintenance of healthy eating behaviors over time. Food labels and strategies that increase visibility and convenience of healthy foods (choice architecture) promote healthier choices, but long-term effectiveness is unknown.

Assess effectiveness of traffic-light labeling and choice architecture cafeteria intervention over 24 months.

Longitudinal pre-post cohort follow-up study between December 2009 and February 2012. Data were analyzed in 2012.

Large hospital cafeteria with a mean of 6511 transactions daily. Cafeteria sales were analyzed for (1) all cafeteria customers and (2) a longitudinal cohort of 2285 hospital employees who used the cafeteria regularly.

After a 3-month baseline period, cafeteria items were labeled green (healthy); yellow (less healthy); or red (unhealthy) and rearranged to make healthy items more accessible.

Proportion of cafeteria sales that were green or red during each 3-month period from baseline to 24 months. Changes in 12- and 24-month sales were compared to baseline for all transactions and transactions by the employee cohort.

The proportion of sales of red items decreased from 24% at baseline to 20% at 24 months (p<0.001), and green sales increased from 41% to 46% (p<0.001). Red beverages decreased from 26% of beverage sales at baseline to 17% at 24 months (p<0.001); green beverages increased from 52% to 60% (p<0.001). Similar patterns were observed for the cohort of employees, with the largest change for red beverages (23%-14%, p<0.001).

A traffic-light and choice architecture cafeteria intervention resulted in sustained healthier choices over 2 years, suggesting that food environment interventions can promote long-term changes in population eating behaviors.