Introduction:
Consumption of fruit and vegetables is associated with a lower risk of obesity, diabetes, hypertension, and cardiovascular disease
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While five or more servings of fruits and vegetables are recommended, only 50% of residents of New York City (NYC) consume two or more servings a day. While food marketing can change individual dietary behaviors, there is limited evidence on the extent to which healthy food marketing strategies—such as community-based and mass-media campaigns—influence fruit and vegetable consumption at the neighborhood level. Agent-based modeling (ABM) has the potential to provide new insights on how healthy food marketing may impact dietary behaviors by simulating interventions, consumption decisions, and interactions among people in different contexts.
Hypothesis:
Healthy food marketing significantly increases consumption of fruit and vegetables in NYC neighborhoods. The impact of healthy food marketing varies across different neighborhoods depending on population characteristics and the local food environment.
Methods:
We developed an ABM that takes into account individual and neighborhood-level factors (e.g., age, gender, education, food environment) and influences of social networks (peers, friends, and family) to predict dietary behaviors of individuals at the neighborhood level. Model parameters were estimated from the Food Attitudes and Behaviors Survey, United States Census data, and previous studies. Healthy food marketing can strengthen positive social norms with regard to dietary behaviors. We simulated two hypothetical healthy food marketing interventions that could improve the influence of positive social norms by 5% and 10%, respectively. We predicted the impact of these interventions on the proportion of the population who consume two or more servings of fruits and vegetables across 34 NYC neighborhoods (defined by the United Hospital Fund) in three years. We validated our model using data from the NYC Community Health Survey.
Results:
The simulation results suggested that the healthy food marketing interventions have the potential to increase the proportion of the population who consume two or more servings of fruits and vegetables over three years: for a 5% improvement on positive social norms, the increase in the proportion was 0.58% - 8.97% by neighborhood; and for a 10% improvement on positive social norms, 2.68% - 13.94% by neighborhood. Exploratory analyses suggested that among population characteristics, a high proportion of population without a high school diploma was associated with lower effectiveness of healthy food marketing in increasing consumption of fruits and vegetables.
Conclusions:
Healthy food marketing may increase consumption of fruits and vegetables in NYC, but more attention to the mechanisms that account for the lower increase in neighborhoods with low educational attainment is needed.
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