GIS for International Applications
Assignment 2: Project Topic Interest
Leila Seradj
29 January 2013
Access to Food and Obesity Levels in Washington, D.C.
Summary:
There is growing body of research on the relationship health outcomes and access to
healthy foods at the neighborhood level. One hypothesis is that economically and socially
disadvantaged neighborhoods have inadequate access to healthy foods, which negatively
affecting dietary quality and health, including obesity. Others conclude that easy access to all
food plays a more important role rising obesity rates than lack of access to healthy foods. This
project aims to see whether there is a relationship between obesity and access to food. It will do
this by examining neighborhood-level data on access to food outlets, obesity levels, income
levels, and race and ethnicity in Washington, D.c.
Spatial/Geographic Questions Related to Topic:
(1) Are individuals living in food deserts more likely to be obese? Additionally, is there a
relationship between the socio-economic and racial/ethnic makeup of a neighborhood and its
obesity rates?
Many studies find a correlation between lower access to food outlets and lower intake
of nutritious foods, which may contribute to obesity. However, a study on food
deserts commissioned by Congress in 2008, the USDA concluded that “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” (ERS Report Summary, “Access
to Affordable and Nutritious Food: Measuring and Understanding Food Deserts and
their Consequences,” June 2009). For this reason, this may be an interesting question
to consider.
(2) How do these neighborhoods with easy access to food outlets fare in terms of obesity levels?
This also addresses the USDA report conclusion cited in question (1). If easy access
to all foods, rather than lack of access to healthy foods, is a more important factor in
explaining rising obesity rates, then one may expect to find comparable obesity levels
in areas with easy access to food.
(3) How has the existence of food outlets changed in the past two decades?
I do not know whether data on food outlets in Washington, D.C. exists dating back to
the 1990s. If it does, given the demographic transition in D.C., I thought this would
be an interesting question to look at.
GIS for International Applications
Assignment 2: Project Topic Interest
Leila Seradj
29 January 2013
References:
(1) Samina Raja, Changxing Ma and Pavan Yadav. “Beyond Food Deserts: Measuring and
Mapping Racial Disparities in Neighborhood Food Environments.” Journal of Planning
Education and Research 2008, 27: 469.
http://jpe.sagepub.com/content/27/4/469.full.pdf+html
This article is helpful in getting me to think about levels of analysis in examining access to
food at the level of neighborhoods within a county, taking into consideration race and ethnicity.
The article’s authors decided to examine availability of food destinations at the neighborhood
level, which required them to look at census blocks rather than census tracts. Also, in their
conclusion, the authors warn that the strategy to “chase after super markets (or grocery stores) to
bring them into minority neighborhoods” poses the risk of putting existing locally-owned food
markets out of business. This may add another dimension to my project, i.e. looking at the
existence smaller food markets, such as corner stores, convenience stores, and ethnic food
markets, and their implications (are prices higher at such stores? Do they fill a gap in what
might have otherwise been a “food desert”? Are they more prevalent in neighborhoods that are
highly represented by families/individuals of a certain income group, race, or ethnicity?)
(2) C.M. Burns and A.D. Inglis. “Measuring food access in Melbourne: Access to healthy and
fast foods by car, bus and foot in an urban municipality in Melbourne.” Health and Place,
2007, 31:4. http://dx.doi.org/10.1016/j.healthplace.2007.02.005
This paper assessed access to healthy and unhealthy foods in Melbourne using a GIS
accessibility program. It examined average travel time to healthy and unhealthy food
destinations by bus, car, and foot. Given that I am looking at an urban location with a highlyutilized public transportation system and in which it is not unusual to not own a car, the methods
used to examine this data may be helpful for my project.
(3) Elizabeth A. Baker, Mario Schootman, Ellen Barnidge, and Cheryl Kelly. “The Role of Race
and Poverty in Access to Foods That Enable Individuals to Adhere to Dietary Guidelines.”
Preventing Chronic Disease 2006, 3:3.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1636719/
This article looked at the relationship between adhering to dietary guidelines and access to
healthy food options in Detroit, taking into consideration differences in racial distribution and
poverty rates within and among neighborhoods. It found that two factors—race and income—
were associated with the location of food outlets: individuals living in mixed or white highpoverty areas and primarily African-American areas (regardless of income) were less likely to
have access to food outlets than individuals in primarily white, higher income communities.
Washington, D.C. is highly segregated by income and race, but certain neighborhoods are
presently undergoing a dramatic demographic shift. This has consequently meant that
neighborhoods that may have been “food deserts” are experiencing an influx of healthier food
options, but their populations may also be shifting.
GIS for International Applications
Assignment 2: Project Topic Interest
Leila Seradj
29 January 2013
(4) Kristian Larsen and Jason Gilliland. “Mapping the evolution of ‘food deserts’ in a Canadian
city: Supermarket accessibility in London, Ontario, 1961–2005.” International Journal of
Health Geographics 2008, 7:16.
http://www.ij-healthgeographics.com/content/7/1/16
This paper takes a unique approach in looking at food availability in a mid-sized
Canadian city by examining the temporal evolution of food deserts. The authors used GIS to
map the locations of supermarkets in London, Ontario in 1961 and 2005 and analyzed the
changing levels of supermarket access in relation to neighborhood location, access to public
transit, and socioeconomic characteristics. If possible and if the data exists, it may be interesting
to look at how the existence food outlets has shifted at the neighborhood level in Washington,
and whether there is any relationship between that change and demographic shifts.
Existing Data Sources:
The USDA Economic Research Service provides free data on food desert census tracts in
the United States. Reference USA may provide data on food destinations. I plan to access U.S.
Census data for population data on ethnicity, vehicle ownership, and income levels.