Who a person is may matter more than where they shop for food in predicting their consumption of unhealthy food, according to a new RAND Corporation study that challenges notions that building supermarkets in "food deserts" can help the nation eat better.
Studying people who live in areas considered to be food deserts, researchers found that more frequent shopping at convenience and neighborhood stores and being younger, male, without a college degree and receiving government food assistance were associated with greater intake of sugar-sweetened beverages, added sugars and discretionary fats. Being older, male and having a college degree were associated with eating more fruits and vegetables.
The social and demographic factors were nearly twice as important as where one shopped for food in predicting consumption of unhealthy food, according to the study published online by the journal Preventive Medicine.
"Our findings suggest that interventions that focus on modifying the food retail environment by opening more stores that sell healthy food will have relatively little impact on reducing consumption of unhealthy food," said Christine Vaughan, lead author of the study and a behavioral scientist at RAND, a nonprofit research organization. "Instead, strategies designed to modify the choices people make about food stand a better chance of reducing consumption of unhealthy foods."
Researchers suggest there is a need for targeted interventions to improve the dietary choices of individuals with sociodemographic characteristics that were associated with unhealthy food consumption. In addition, policymakers should consider strategies that have been shown in previous research to change behavior across shopping environments, such as imposing taxes on sugary soda products and limiting the display of unhealthy foods in all types of stores.
There long has been debate about the role that the food shopping environment has on the public's dietary habits and how that relates to the nation's obesity problem. Much attention has focused on opening new supermarkets in food deserts — neighborhoods that do not have easy access to full-service supermarkets.
The RAND findings are from an ongoing project that is studying food consumption and food shopping in two low-income, predominately African American neighborhoods in Pittsburgh that long had been considered food deserts.
Researchers surveyed 1,372 households in the areas during 2011, asking residents about their dietary habits, including consumption of sugar-sweetened beverages, added sugars, discretionary fats such as butter, and fruit and vegetables, and food shopping patterns.
The study found that sociodemographic factors had the strongest association with the types of food people consumed. Being younger and male significantly predicted greater intake of sugar sweetened beverages, added sugars and discretionary fats. Being younger also predicted less consumption of fruits and vegetables. Lacking a college degree was significantly associated with greater consumption of sugar-sweetened beverages and discretionary fats, and lower fruit and vegetable consumption. Receiving Supplemental Nutrition Assistance Program benefits was significantly associated with greater consumption of added sugars.
To determine the types of food available to residents, researchers audited the 24 food stores in the study neighborhoods and 14 food venues outside both the neighborhoods where residents reported doing major food shopping. These included outlets such as convenience stores, wholesale clubs, supermarkets, and fruit and vegetable stands.
Researchers found that nearly all store types emphasized unhealthy food over healthy food and scored the venues based on product placement of unhealthy versus healthy foods. Unhealthy stores were those that had unhealthy food dominating the view from the main entrance and had more displays promoting unhealthy food rather than healthy food.
Establishments grouped into the unhealthy category were convenience stores, neighborhood stores and dollar stores. Moderately unhealthy stores included discount grocery stores, supercenters and wholesale clubs. Healthy stores included full-service supermarkets, specialty grocery stores, and fruit and vegetable shops. But even some of the healthy stores prominently displayed unhealthy food, according to researchers.
Shopping more frequently at convenience stores was significantly associated with greater consumption of added sugars, and buying more goods from neighborhood stores predicted greater intake of sugar sweetened beverages and discretionary fats. Buying more food at supercenters was significantly associated with greater intake of discretionary fats.
Not surprisingly, shopping more often at specialty grocery stores was linked to greater consumption of fruits and vegetables.
"While both the food shopping environment and sociodemographic characteristics were associated with eating more unhealthy food, the personal characteristics were more important," said Tamara Dubowitz, co-author of the study and a RAND senior policy researcher. "This work suggests we need to do more than just trying to eliminate food deserts. We need strategies that can encourage healthy eating and discourage unhealthy eating."
Support for the study was provided by the National Cancer Institute. Other authors of the study are Rebecca Collins, Madhumita Ghosh-Dastidar and Robin Beckman.
RAND Health is the nation's largest independent health policy research program, with a broad research portfolio that focuses on health care costs, quality and public health preparedness, among other topics.