The committee used the framework to understand the process by which households participating in SNAP may or may not achieve the program goals, as well as how program characteristics affect this process. Nonetheless, the framework has some important limitations. As discussed above, it focuses only on the proximal goals of improving food security and access to a healthy diet and does not explicitly cover longer-term outcomes that may be most important, including health outcomes such as chronic disease. A related issue is that the framework represents the program goals simply as binary measures, with participants either achieving or failing to achieve them. Especially in the case of access to a healthy diet, this representation fails to capture the multiple dimensions of the complex relationship between diet and health.
Another limitation of the framework is its linearity; it represents complex household processes for purchasing and consuming specific foods as resulting in a straightforward way from a set of exogenous influences (total resources, individual/household factors, and environmental factors). In reality, the process probably is not entirely linear, and there are likely various feedback mechanisms at work. For example, not only may the foods participants consume be affected by their individual tastes and preferences, but their tastes and preferences themselves may be affected by the foods they consume. Similarly, food insecurity and lack of a healthy diet increase the risk for chronic diseases, such as diabetes and hypertension, that in turn affect participants’ consumption choices and even their access to foods needed to meet their needs.
Despite the framework’s limitations in capturing subtleties in how households make decisions about what foods to purchase and consume, the committee believes it provides an adequate overview of this process. This overview serves as a useful way to understand the factors that affect food security and access to a healthy diet, how SNAP allotments affect household choices, and how the allotments may or may not be adequate for allowing participants to achieve the program goals.
The remainder of this report is structured according to the framework depicted in Figure 1-2. First, however, Chapter 2 provides historical information about the development of the SNAP program, as well as background on the program and its goals. Chapter 3 presents evidence on the extent to which SNAP participants achieve the program goals, as well as on household purchasing patterns. Chapter 4 addresses the individual and household factors that affect participants’ food choices, along with some