(P22-046-23) Study Protocol: Feasibility of a Whole Foods Dietary Guidelines-Based Intervention for Type 2 Diabetes Prevention in High-Risk Families

Objectives: It is unknown if a family-centered whole foods diet can improve diet quality and prevent type 2 diabetes (T2D). This protocol describes the recruitment and process methods of an ongoing study testing the feasibility and acceptability of a weight-maintaining whole foods diet in adults with prediabetes and their high-risk for T2D offspring.

Methods: Whole Foods for Prediabetes is a single-arm pre-post experimental controlled-feeding study. Approximately 8-12 adults 25-59 years with prediabetes and 1-2 biological offspring 6-17 years will participate in a 2-week family-based intervention of a whole foods diet adapted from the 2020-2025 Dietary Guidelines for Americans (25%:45%:30% daily calories from protein: carbohydrates: fats). Families will receive 1) 2-weeks of menu/grocery delivery with enough food to feed up to 4 individuals (3 meals, 1-2 snacks daily), and 2) weekly diet counseling by a registered dietitian. The primary outcome measures include 1) study feasibility assessed via participant retention rates ( >50% complete study at 2-weeks) and completion of intervention requirements (≥80% completion in 50% of adults) and 2) acceptability assessed via participant feedback during a post-study focus-group session. Secondary outcomes include anthropometric measurements of adult-child dyads (weight, height, body mass index [BMI] including BMI% and z-scores, and waist circumference) and change in pre-post child diet quality using 24-hour dietary recall information to estimate Healthy Eating Index (HEI-2020) scores. Paired (dependent sample) t-tests will be used to compare differences between baseline and 2-week outcomes for anthropometrics measurements (within group comparisons), and child HEI-2020 total and sub-scores. Qualitative focus group interviews will be conducted and analyzed using thematic analysis to assess diet satisfaction and barriers and facilitators that influenced diet adherence.

Results: The study has received Institutional Review Board approval. Recruitment activities have started, and data collection is ongoing.

Conclusions: This study will generate preliminary data to inform a future randomized clinical trial to test the efficacy and sustainability of a whole foods diet in high-risk for T2D families.

Funding Sources: AHRQ, NIH, Vanderbilt School of Nursing