Addressing Food Access and Physical Activity to Improve Diabetes Prevention Outcomes Among Underserved African Americans

This study is a cluster-randomized clinical trial designed to evaluate the effectiveness of an enhanced, culturally, socially, and structurally tailored Diabetes Prevention Program (E-DPP) compared to a standard culturally tailored DPP (S-DPP) among African American adults with prediabetes residing in low-income, socially vulnerable communities. The trial will enroll approximately 408 participants across 12 community-based sites (churches), which will be randomized to deliver either S-DPP or E-DPP to minimize contamination across intervention conditions.

Both intervention arms are grounded in the evidence-based DPP lifestyle intervention and incorporate cultural tailoring strategies to improve relevance and acceptability in African American communities. The enhanced intervention builds upon this foundation by explicitly addressing multilevel social determinants that influence engagement in healthy eating and physical activity. Specifically, E-DPP integrates structural supports to improve access to healthy foods and safe, low-cost physical activity opportunities, alongside strategies to address social stigma related to obesity, poverty, and food insecurity.

The E-DPP includes additional components delivered during and between sessions. These include provision of fruits and vegetables during sessions, experiential activities focused on healthy food selection and budgeting, and facilitated linkage to community food resources such as food pantries and assistance programs. Physical activity support includes structured in-session exercise and guidance on accessing community-based physical activity programs. Participants in the E-DPP arm will also receive tailored text messaging designed to reinforce behavior change, promote utilization of community resources, and reduce stigma-related barriers to engagement.

The intervention is delivered over a 12-month period, with assessments conducted at baseline, 6 months, and 12 months. A community-engaged approach informs intervention design and implementation, ensuring alignment with local context and resources. The study is guided by theoretical frameworks that emphasize the role of social and structural determinants in shaping health behaviors and outcomes.

In addition to evaluating intervention effects, the study will examine potential mediators and moderators of weight loss, including social determinant-related stressors, access to resources, and psychosocial factors. A concurrent process evaluation will assess intervention fidelity, dose, participant engagement, acceptability, and feasibility, as well as cost-related considerations. These data will inform identification of key intervention components and support future scalability and dissemination of the enhanced program in underserved communities.

Inclusion criteria

• Members of a participating church or user of a participating church's outreach services
• Age 18 years or older
• Prediabetic (score of 5 or higher in the National Diabetes Prevention Program Risk Score or ([body mass index > 24 or history of gestational diabetes] and (5.7-6.4 A1v, 100-125 mg/dL fasting plasma glucose, or 140-149 mg/dL oral glucose tolerance test)

Exclusion criteria

• Individuals who are pregnant, breastfeeding or planning to become pregnant in the next year
• Individuals with unsafe blood pressure levels (160 systolic or higher or 100 diastolic or higher) without a medical clearance firn
• Individuals who are not able to engage in low-impact physical activity
• Individuals who do not speak English
• Individuals who live in a household with a participant in this study at a different church