A Systematic Review of Dietary Interventions for Low-Income Populations

Introduction: Recent enacted reductions to the Supplemental Nutrition Assistance Program (SNAP) benefits will eliminate access to food stamps for nearly 1 million Americans. Given this policy change and the well-documented effects of diet on health outcomes, continued efforts are needed to ensure historically disadvantaged populations are included in and benefit from interventions developed to encourage adherence to nutritionally adequate diets. We reviewed the extant literature to characterize the quantity and quality of studies evaluating dietary modification interventions for low-income populations.

 Methods: Searches of online databases, reference lists and past reviews were conducted. Articles reporting the results of trials designed specifically for low-income populations, enrolling adults, and using a concurrent-control design were included in the review. Two trained coders independently extracted data from each report; the CALO-RE taxonomy was used to identify the specific behavior change components employed.

 Results: Forty-seven articles from 1976 to 2013 were included; six described research conducted outside the US. Steps taken to tailor the intervention to a low-income population included formative research, pretesting, and reading level adjustments; the tailoring process was unclear in 14 reports (29.8%). Most reports operationalized ‘low-income’ by geography or receipt of public assistance; only eleven reports (23.4%) used a financial metric. The most commonly used approaches to behavior change were through instruction (70.0%), provision of normative information (42.6%), and behavioral modeling (31.9%). 

 Discussion: A more refined definition of ‘low-income’ and population-specific tailoring is needed to address dietary modification among underserved populations.  Interventions incorporating hands-on learning, social support, and relapse prevention are recommended.