Background: Effective strategies are needed to address obesity, particularly among minority and low-income individuals.
Purpose: To test whether a two-phase point-of-purchase intervention improved food choices across racial, socioeconomic (job type) groups.
Design: A 9-month longitudinal study from 2009 to 2010 assessing person-level changes in purchases of healthy and unhealthy foods following sequentially introduced interventions. Data were analyzed in 2011.
Setting/participants: Participants were 4642 employees of a large hospital in Boston MA who were regular cafeteria patrons.
Interventions: The first intervention was a traffic light-style color-coded labeling system encouraging patrons to purchase healthy items (labeled green) and avoid unhealthy items (labeled red). The second intervention manipulated "choice architecture" by physically rearranging certain cafeteria items, making green-labeled items more accessible and red-labeled items less accessible.
Main outcome measures: Proportion of green- (or red-) labeled items purchased by an employee. Subanalyses tracked beverage purchases, including calories and price per beverage.
Results: Employees self-identified as white (73%); black (10%); Latino (7%); and Asian (10%). Compared to white employees, Latino and black employees purchased a higher percentage of red items at baseline (18%, 28%, and 33%, respectively, p<0.001) and a lower percentage of green (48%, 38%, and 33%, p<0.001). Labeling decreased all employees' red item purchases (-11.2%, 95% CI= -13.6%, -8.9%) and increased green purchases (6.6%, 95% CI=5.2%, 7.9%). Red beverage purchases decreased most (-23.8%, 95% CI= -28.1%, -19.6%). The choice architecture intervention further decreased red purchases after the labeling. Intervention effects were similar across all race/ethnicity and job types (p>0.05 for interaction between race or job type and intervention). Mean calories per beverage decreased similarly over the study period for all racial groups and job types, with no increase in per-beverage spending.
Conclusions: Despite baseline differences in healthy food purchases, a simple color-coded labeling and choice architecture intervention improved food and beverage choices among employees from all racial and socioeconomic backgrounds.
Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.