Marie-Antoinette is famously believed to have said “Let them eat cake” when she was told that her French subjects had no bread to eat.  For some Americans, finding either bread or cake can be a struggle when no food stores are close by. Being in such a scenario is often referred to as a “food desert.” 

 The USDA Economic Research Service has recently published a paper called Access to Affordable and Nutritious Food: Measuring and Understanding Food Deserts and Their Consequences.  The report is not necessarily an indictment of the way things are now and a  call to action – which may disappoint some – but it does provide some parameters of the issue. From the report:

Access to a supermarket or large grocery store is a problem for a small percentage of households. Results indicate that some consumers are constrained in their ability to access affordable nutritious food because they live far from a supermarket or large grocery store and do not have easy access to transportation. Three pieces of evidence corroborate this conclusion: Of all households in the United States, 2.3 million, or 2.2 percent, live • more than a mile from a supermarket and do not have access to a vehicle.

Supermarkets and large grocery stores have lower prices than smaller stores. A key concern for people who live in areas with limited access is that they rely on small grocery or convenience stores that may not carry all the foods needed for a healthy diet and that may offer these foods and other food at higher prices. This report examines whether prices of similar foods vary across retail outlet types and whether the prices actually paid by consumers vary across income levels. These analyses use proprietary household-level data that contain information on food items  purchased by approximately 40,000 demographically representative households across the United States. Results from these analyses show that when consumers shop at convenience stores, prices paid for similar goods are, on average, higher than at supermarkets.

Low-income households shop where food prices are lower, when they can. Findings also show that food purchases at convenience stores make up a small portion of total food expenditures (2 to 3 percent) for low-income consumers. Low- and middle-income households are more likely to purchase food at supercenters, where prices are lower. Administrative data on SNAP benefit redemptions from 2008 show that 86 percent of SNAP benefits were redeemed at supermarkets or large grocery stores.

Research that considers the prices paid for the same food across household income levels indicates that while some of the very poorest households—those earning less than $8,000 per year—may pay between 0.5 percent and 1.3 percent more for their groceries than households earning slightly more, households earning between $8,000 and $30,000 tend to pay the lowest prices for groceries, whereas higher income households pay significantly higher prices. The study also examined food shopping behavior and the types of food purchased for SNAP participants and other low-income households. Data from the 1996/1997 NFSPS show that SNAP participants were, on average, 1.8 miles from the nearest supermarket.
However, the average number of miles both SNAP participants and eligible nonparticipants traveled to the store most often used was 4.9 miles. These same data show that SNAP participants who did not shop at  supermarkets purchased less noncanned fruit,  noncanned vegetables, and milk than SNAP participants who shopped frequently at a supermarket.

Easy access to all food, rather than lack of access to specific healthy foods, may be a more important factor in explaining increases in obesity. Many studies find a correlation between limited food access and lower intake of nutritious foods. Data and methods used in these studies, however, are not sufficiently robust to establish a causal link between access and nutritional outcomes.

That is, other explanations cannot be eliminated as the cause of lower intake. A few studies have examined food intake before and after healthy food options become available (either within existing stores or because new stores opened). The findings are mixed—some show a small but positive increase in consumption of fruits and vegetables, while others show no effect. The causal pathways linking limited access to nutritious food to measures of overweight like Body Mass Index (BMI) and obesity are not well understood. Several studies find that proximity of fast food restaurants and supermarkets are correlated with  BMI and obesity

But increased consumption of such healthy foods as fruits and vegetables, low-fat milk, or whole grains does not necessarily lead to lower BMI. Consumers may not substitute away from less healthy foods when they increase their consumption of healthy foods. Easy access to all food, rather than lack of access to specific healthy foods, may be a more important factor in explaining increases in BMI and obesity.

Understanding the market conditions that contribute to differences in access to food is critical to the design of policy interventions that may be effective in reducing access limitations. Access to affordable and nutritious food depends on supply (availability) and consumer demand. Consumer behavior, preferences, and other factors related to the demand for some foods may account for differences in the types of foods offered across different areas. Food retailer behavior and supply-side issues such as higher costs to developing stores in underserved areas may also explain variation across areas in which foods are offered and what stores offer them.

If high development costs serve as a barrier to entry for supermarkets in some areas with low access, then subsidy programs or restructured zoning policies may be effective solutions. If consumer demand factors, such as inadequate knowledge of the nutritional benefits of specific foods, contribute to differences in access by reducing demand, then a public health campaign may be a preferred strategy. Several local and State-level efforts are underway that could provide the basis for a better understanding of the types of interventions that may work best.

Food has been used as a tool for community development. Projects such as farmers’ markets, community gardens, promotion of culturally specific foods for ethnic minorities and Native Americans, local food production and promotion, youth agricultural and culinary training programs, and many other types of programs have all been implemented in a variety of settings, both urban and rural. USDA’s Community Food Projects Competitive Grant program has much experience in funding and nurturing such programs.

The current state of research is insufficient to conclusively determine whether some areas with limited access have inadequate access. Future research should consider improved methods to measure access levels, availability, and prices of foods faced by individuals and areas. More research is needed to understand how access, availability and price affect the shopping and consumption behaviors of consumers.
Data linking information on the types of foods consumers purchase and eat with measures of consumers’ levels of access and the prices they face could help explain the economic consequences of food access. Studies that use improved methods and data to determine how food access affects diet, obesity, and other health outcomes are also needed to help explain the health consequences of food  access.

TK: The study makes some interesting observations but does little to create enthusiasm for the concept that greater access to fruits and veggies will create healther choices by consumers in underserved areas. It also thows a little cold water on the idea - tacitly embraced by the More Matters campaign - that increased f/v consumption will  lead to lower BMI among consumers.  If you would like to see a study that says, "No more research is needed - action is required."   - this is not the study you are looking for. Of course, economists typically say nothing of that sort anyway.