Whole Prediabetes: A Family-Centered Whole Foods Diet in Adults With Prediabetes and Their Offspring

This study will address the following aims:

Aim 1: Design a family-centered whole foods diet adapted from the 2020-2025 DGA framework for 8-12 families that include an index parent (25-59 years) with medically managed prediabetes and their biological offspring (6-17 years).

Aim 2: Test the feasibility, acceptability, enrollment, retention, and completion rates of a 2-week family-centered whole foods-based diet for 8-12 families that include an index parent (25-59 years) with medically managed prediabetes and their biological offspring 6-17 years.

Aim 3: Estimate and compare differences in baseline and 2-week body mass change (e.g., BMI, BMI percentiles and Z-scores, waist circumference) and diet quality for the index parent and their enrolled biological offspring.

This dietary program is based on empirical evidence showing that a diet pattern that favors minimally processed and whole foods (e.g., whole grains, fruits, vegetables, nuts) in contrast to diet patterns with greater consumption of highly refined and ultra-processed foods are attributed to greater reductions in HbA1c and fasting plasma glucose and a reduced risk for T2D. This evidence comes primarily from prospective cohort and clinical studies of 1) adult populations without diabetes (including type 2 and pre-diabetes) and 2) adult populations with active T2D. Studies of family dietary interventions for transgenerational T2D prevention are lacking.

Studies have focused primarily on structured diet patterns such as the Mediterranean style, Vegetarian or Vegan, Dietary Approaches to Stop Hypertension (DASH), carbohydrate-restricted, and low-fat. Evidence supports that the diet patterns most effective for T2D risk reduction focused on primarily whole food consumption (e.g., Mediterranean-style, Vegetarian, and DASH). Yet, less attention has been given to studying the effectiveness of the Dietary Guidelines for American's (DGA) diet pattern which forms the basis of nutrition advice in the U.S. and is the guiding nutrition framework used for federal nutrition policy. Moreover, a benefit of the recent DGA is its customizable approach to diet.

Recognizing the importance of a whole foods structured diet and the recent shift of the Dietary Guidelines for American's DGA diet pattern towards a customizable, family-centered, whole foods approach, studies that test the effectiveness of a DGA-structured diet for T2D risk reduction should be prioritized. Before conducting efficacy and effectiveness trails, pilot data is needed to determine the feasibility and acceptability of using this family-centered diet approach in a population at "high risk" for T2D. Applying a family-lens where a transgenerational approach can be used to prevent T2D is necessary.

Therefore, this program aims are to design and test the feasibility of delivering a whole foods diet pattern using a family centered approach in a population at risk for T2D- adults with prediabetes and their "at-risk" biological offspring.

Eligibility Criteria:
Inclusion Criteria:

For this study, eligible adults will be those that:

1. are 25 to 59 years of age at time of initial screen and identify as a parent to at least one (two max) biological child or adolescent 6-17 years;
2. have a body mass index of between ≥23kg/m2 to \<40kg/m2;
3. have prediabetes (based on American Diabetes Association criteria of either fasting plasma glucose of ≥100 mg/dL, HgbA1c 5.7-6.4%, or 2-hour plasma glucose during 75-g oral glucose tolerance test \[OGTT\] 140 mg/dL to 199 mg/dL) reported within the last 6 months and confirmed by the participants medical records;
4. have no special dietary restrictions or food allergies that would prohibit consumption of a variety of foods/beverages;
5. are English speaking;
6. reside within the greater Nashville, TN area;
7. are without medical conditions that would limit participation in a diet-related study (e.g., tube feeding, dysphagia, severe food allergy causing anaphylaxis);
8. are able to participate in a two-week dietary program that requires home preparation/cooking for all meals and snacks;

For this study, eligible offspring (child(ren)/ adolescent(s)) will be those that:

1. Are 6-17 years at time of initial screen;
2. Have an index parent with prediabetes that is actively enrolled in the program;
3. have body mass index ≥5th percentile for age and gender on standardized CDC growth curves;
4. have no special dietary restrictions or food allergies that would prohibit consumption of a variety of foods/beverages;
5. have parental commitment to participate in a two-week research study;
6. are English speaking;
7. reside within the greater Nashville, TN area and live at home with their index parent during duration of 2- week study;
8. are without medical conditions that would limit participation in a diet-related study (e.g., tube feeding, dysphagia, severe food allergy causing anaphylaxis);
9. are able to participate in a two-week dietary program that includes at least dinner and snacks provided during after-school hours;

Exclusion criteria:

Adult exclusion criteria include:

1. adults outside the specified age range of \<25 years or \>59 years;
2. adults whose body mass index is \<23kg/m2 or those with a body mass index ≥40kg/m2 as that degree of morbid obesity represents a different phenotype where dietary behavioral intervention alone may not be sufficient to achieve weight loss);
3. are not currently undergoing routine medical supervision by a licensed healthcare provider (i.e., MD, NP, PA) for a complicated diagnosis of prediabetes that requires routine glycemic monitoring or frequent healthcare visits for management/treatment;
4. adults actively participating in any type of weight loss program (dietary or physical activity) or those who participate in regular (≥120 minutes per week) moderate to vigorous physical activity (as requirements of the program include assessing weight change as a result of the diet);
5. adults with a prior history of type 2 diabetes;
6. adults who are not English speaking;
7. adults with special dietary restrictions, food allergies, or medical conditions that prohibit participation in a diet-related study;
8. adults with serious mental or neurologic illness that impairs ability to consent/participate;
9. women who are pregnant or nursing due to increased metabolic state requiring greater energy requirements;
10. adults currently taking medications to treat diabetes or to promote weight loss;
11. adults living outside the greater Nashville, TN area;
12. adults with poor visual acuity (corrected vision worse than 20/50 with Rosenbaum Screener);
13. adults who do not otherwise meet the eligibility criteria listed in sections above as determined by pre-screen;

Offspring (child\[ren\] and adolescent\[s\]) exclusion criteria include:

1. children/adolescents outside the specified age range of \<6 years or \>17 years;
2. children/adolescents whose body mass index is \<5th percentile for age and gender on standardized CDC growth curves;
3. children/adolescents who do not have an eligible index parent participating in the study;
4. children who do not have parental commitment to participate consistently for two-weeks;
5. children/adolescents with a current or past diagnosis of diabetes mellitus (including prediabetes and type-2);
6. children/adolescents who are not English speaking;
7. children/adolescents with special dietary restrictions, food allergies, or medical conditions that prohibit participation in a diet-related study;
8. children/adolescents who display dissenting behaviors during baseline data collection;
9. children/adolescents actively participating in any type of weight loss program (medical or lifestyle);
10. children/adolescents who do not otherwise meet the eligibility criteria listed in sections above as determined by pre-screen;