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

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 child or adolescent 6-18 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) 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); 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 6-18 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); 9. are able to participate in a 12-week dietary program that includes at least dinner and snacks provided during after-school hours; Exclusion Criteria: Adult exclusion criteria include: 1. Adults who's 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 \>59 years; 3. 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); 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 (child\[ren\] and adolescent\[s\]) exclusion criteria include: 1. children/adolescents outside the specified age range of \<6 years or \>18 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 12-weeks 5. children/adolescents who are not English speaking or have limited English-language proficiency; 6. children/adolescents with special dietary restrictions, food allergies, or medical conditions that prohibit participation in a diet-related study; 7. children/adolescents who display dissenting behaviors during baseline data collection; 8. children/adolescents actively participating in any type of weight loss program (medical or lifestyle); 9. children/adolescents who do not otherwise meet the eligibility criteria listed in sections above as determined by pre-screen;