The development and testing of a single-arm feasibility and acceptability study of a whole foods diet intervention for adults with prediabetes and their offspring.

backgroundDiet is considered a first-line treatment option for prediabetes, a condition that affects 96 million United States (U.S.) adults. Diet patterns that prioritize whole foods (e.g., Mediterranean) are currently recommended to treat prediabetes. However, no studies have tested whether a U.S.-style diet pattern that prioritizes whole foods can be used to treat prediabetes. The purpose of this study was to assess the feasibility and acceptability of a whole foods diet for adults with prediabetes and their offspring prior to conducting a larger clinical trial.

methodsA 2-week single-arm pre-post experimental controlled-feeding intervention of a 2020-2025 Dietary Guidelines for Americans adapted whole foods diet (e.g., primarily focused on foods that have undergone limited processing or refinement) was conducted in adults (25-59 years) with prediabetes and their biological offspring (6-17 years). Families received 2 weeks of menus and grocery delivery and weekly counseling by a registered dietitian. Families were invited to attend an optional focus group session. Feasibility was based on having a ≥ 50% family completion rate with ≥ 80% completion of study outcomes. Measures included adult-child anthropometrics (weight [kg], body mass index [BMI] including BMI% and Z-scores for offspring, waist circumference [cm]) and child diet quality estimated using the 2015 Healthy Eating Index (HEI) from a single random food record. Wilcoxon signed rank was used to compare differences between baseline and 2-week anthropometrics measures and offspring total HEI scores. Qualitative data were analyzed using thematic analysis to understand factors attributed to diet adherence and acceptability.

resultsEight families enrolled (n = 8 adults, n = 12 offspring), with 7 families completing the study (12% attrition) and completing 100% of study outcome measures. Adults experienced a median weight loss of - 1.0 kg from baseline to 2 weeks (79.5 kg to 78.5 kg). Offspring had a 24-point increase in total 2015 HEI scores (median difference 50 to 74). Focus group participants (n = 4 adults) reported being satisfied with the program and expressed a willingness to continue the diet despite identified barriers.

conclusionsA whole foods diet that provides dietary support was found to be feasible and acceptable for families at risk for T2D. Future studies are needed to test the effects of the diet on prediabetes outcomes, diet quality, and diet adherence in adults and families.

trial registrationNCT05483972 at ClinicalTrials.gov. Registered July 25, 2022. https://clinicaltrials.gov/study/NCT05483972?cond=prediabetes&term=whole%20foods%20&rank=1.