This study is the first step in understanding the influence of the food environment on food choice and diet quality in Hispanic families who live in high- or persistent-poverty areas where public transportation is limited or nonexistent and many residents lack access to a vehicle.
Families that reside in areas of persistent poverty face individual, family, and environmental challenges to food security and healthful eating. The economic and social burden posed by nutrition-related chronic health conditions (for example, obesity, cardiovascular disease, and diabetes) is tremendous. The burden becomes greater for children and adults who are poor, Hispanic, reside in colonias along the Texas border with Mexico, and face greater vulnerability to food insecurity, poor nutritional health, and adverse health outcomes. Personal, structural, and neighborhood characteristics serve as either barriers or enhancements to lifestyle behaviors, such as physical activity or healthy eating. Residents of colonias face the greatest structural and neighborhood disadvantage, such as substandard housing areas, inadequate roads, and poor access to community food resources. These disadvantages make it particularly difficult for children and adults in these areas to initiate or maintain lifestyle changes that are critical for the prevention of disease conditions. Thus, the goals of this study were as follows:
- Assess the food environment through direct observation in targeted colonia census block groups (CBGs) in Hidalgo County.
- Determine the geospatial characteristics of food environment accessibility and examine the association between neighborhood deprivation (CBG-level neighborhood socioeconomic status) and locational disadvantage for access to food stores and foodservice places.
The study area included 197 census block groups, an urban and rural land area of approximately 772 square miles, and a population of more than 423,000 people (87 percent Hispanic). The types of food stores and foodservice places were defined using a modified version of the 2002 North America Industry Classification System (NAICS) definitions.
Food stores were distinguished as being fixed or mobile:
- Supermarkets and grocery stores.
- Convenience stores or food marts.
- Discount stores (general merchandise and some perishable and nonperishable foods) and
- beverage stores (with some perishable and nonperishable foods),
- Pharmacies and drug stores (with some perishable and nonperishable foods).
- Specialty food stores (for example, meat markets, fish and seafood markets, fruit and vegetables markets, or baked goods not for immediate consumption).
Foodservice places were classified as follows:
- Full-service restaurants (patrons order and are served while seated and pay after eating).
- Fast food restaurants (limited-service where patrons order or select items and pay before eating).
- Cafeteria or buffet.
- Snack and nonalcoholic beverage bars (for example, ice cream, frozen yogurt, snow cones, coffee, or juices for consumption on or near premises).
- Drinking places (provide limited food service).
- Microenterprises, such as a food stand that offers food for the public and operates secondary to a nonfood-related business (for example, a repair shop, hardware store, or beauty salon) or residence.
Observers were trained to use Global Positioning System technology for enumerating and geocoding all food stores and foodservice places at the level of individual address. Observers also conducted unobtrusive outside audits using a structured checklist through direct observation in systematically driven CBGs. Neighborhood (CBG-level) deprivation was determined through construction of an index of socioeconomic variables from the 2000 U.S. Census and categorized from low to very high deprivation. Locational disadvantage was determined through calculations of network distance from CBG centroid to the nearest food store and foodservice place. Stability and difference in locational disadvantage between types of food stores and foodservice places was examined.
Improved knowledge about the food environment is essential for combining environmental approaches with traditional health interventions and food assistance programs to make it easier for individuals to make healthier food choices.
This study identified and geocoded 971 different food stores and foodservice places through direct observation. Of the 18 supermarkets and grocery stores, 10 were locally owned, 2 were rated as being medium-sized, and 5 were classified as small grocery stores. The study identified 255 convenience stores. Almost 65 percent of all convenience stores marketed gasoline, 19.5 percent offered drive-through shopping, 47 percent marketed fast food items, and 23 percent marketed grocery items. Of the 97 specialty food stores, 31 percent were fruit and/or vegetable markets and 35 percent were baked goods stores. Almost 27 percent of the specialty stores did not have a fixed location. There were 204 foodservice places (21 percent of all food stores and foodservice places) that exclusively sold fast food items, 44 percent of which were national chain stores. In areas of high or very high neighborhood deprivation, an average of 15-16 percent (CBG range 2.7-53.0 percent) of households did not have access to a vehicle.
The average network distance from the center of the CBG to the nearest supermarket/grocery store was 2.7 miles (median 2.3 miles) and ranged from 0.18 mile to 14.9 miles. The average distance to the nearest large supermarket was 3.0 miles (median 2.7 miles), and the average distance to the nearest convenience store was 1.1 miles (median 0.90 mile; range 0.05-4.8 miles). Almost 32 percent (n=63) of all CBGs experienced very high locational disadvantage for access to a large supermarket. Among CBGs with very high locational disadvantage, distance to the nearest supermarket/grocery store increased significantly with greater deprivation. Low deprivation CBGs were an average of 4.1 miles to the nearest supermarket/grocery store, medium deprivation CBGs 4.5 miles, high deprivation CBGs 5.5 miles, and very high CBGs 6.0 miles (p <0.01). After combining categories of locational disadvantage for supermarkets/grocery stores with convenience stores, overall locational disadvantage for food stores was determined. Over 20 percent of CBGs (n=40) were classified as CBGs with both high food stores and foodservice places locational disadvantage.