Whole Food for Families: A Pilot RCT of a Dietary Guidelines-Based Intervention to Prevent Type 2 Diabetes

For this study, eligible adults with prediabetes 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 offspring 6-26 years or identify as a spouse/partner to an adult 25-64 years;
2. have a body mass index of between ≥23kg/m2 to ≤45kg/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) with recent lab values reported within the prior 6-12 months and confirmed by an HbA1c A1cNow+ collected prior to enrollment (*see comment below);
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 in Greater Nashville Tennessee and willing to come to Vanderbilt campus and Vanderbilt University Medical Center for required study visits;
7. are without medical conditions that would limit participation in a diet-related study (e.g., tube feeding, dysphagia, severe food allergy causing anaphylaxis; history of or active eating disorder);
8. are able to participate in a 12-week dietary program that requires home preparation/cooking for meals and snacks;

For this study, eligible offspring will be those that:

1. Are 6-26 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 12-week research study
6. are English speaking;
7. reside in the Greater Nashville Tennessee area and live at home with their index parent during the duration of 12- 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, history or active eating disorder);
9. are able to participate in a 12-week dietary program that includes at least dinner and snacks provided during after-school hours;

For this study, eligible spouse/partner will be those that:

1. Are 25-64 years at time of initial screen;
2. Be considered a spouse/partner of an adult with prediabetes that is actively enrolled in the program;
3. have no special dietary restrictions or food allergies that would prohibit consumption of a variety of foods/beverages;
4. are English speaking;
5. reside in the Greater Nashville Tennessee area and live in the home of the enrolled adult with prediabetes during the duration of 12- week study;
6. are without medical conditions that would limit participation in a diet-related study (e.g., tube feeding, dysphagia, severe food allergy causing anaphylaxis, history or active eating disorder);

Adult with prediabetes exclusion criteria include:

1. Adults whose HbA1c test is outside of the HbA1c range during screening* (see details related to screening results)
2. adults outside the specified age range of <25 years or >64 years;
3. adults whose body mass index is <23kg/m2 or those with a body mass index ≥46kg/m2 as that degree of morbid obesity represents a different phenotype where dietary behavioral intervention alone may not be sufficient to achieve weight loss);
4. receiving care by a 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;
5. adults actively participating in any type of weight loss program (dietary or physical activity)
6. adults with a prior history of type 2 diabetes;
7. adults who are not English speaking or have limited English-language proficiency;
8. adults with special dietary restrictions, food allergies, or medical conditions that prohibit participation in a diet-related study;
9. adults with serious mental or neurologic illness that impairs the ability to consent/participate;
10. women who are pregnant or nursing due to increased metabolic state requiring greater energy requirements;
11. adults currently taking medications to treat diabetes or to promote weight loss;
12. adults living outside Greater Nashville Tennessee or who are unwilling to travel to Vanderbilt for study visits;
13. adults who do not otherwise meet the eligibility criteria listed in sections above as determined by pre-screen;

Offspring exclusion criteria include:

1. offspring outside the specified age range of <6 years or >26 years;
2. offspring (under 18 years) whose body mass index is <5th percentile for age and gender on standardized CDC growth curves;
3. offspring who do not have an eligible index parent participating in the study;
4. children (under 18 years) who do not have parental commitment to participate consistently for 12-weeks
5. offspring who are not English speaking or have limited English-language proficiency;
6. offspring with special dietary restrictions, food allergies, or medical conditions that prohibit participation in a diet-related study;
7. offspring with active or history of eating disorder;
8. children/adolescents (under 18 years) who display dissenting behaviors during baseline data collection;
9. offspring who do not otherwise meet the eligibility criteria listed in sections above as determined by pre-screen;

Spouse/partner exclusion criteria include:

1. Spouse/partner outside the specified age range <25 year or ≥65 years;
2. Does not identify as a spouse/partner of the adult with prediabetes that plans to be enrolled in the program;
3. Spouse/partner with special dietary restrictions or food allergies that would prohibit consumption of a variety of foods/beverages;
4. Spouse/partner who are not English speaking or have limited English-language proficiency;
5. Spouse/partner who does not reside in the Greater Nashville Tennessee area and/or does not live in the home of the enrolled adult with prediabetes during the duration of 12- week study;
6. Spouse/partner with medical conditions that would limit participation in a diet-related study (e.g., tube feeding, dysphagia, severe food allergy causing anaphylaxis, history or active eating disorder);