Prediabetes
Conditions
Keywords
prediabetes, diet, nutrition, Mediterranean diet, cardiovascular disease
Brief summary
The purpose of this research study is to determine if a healthy Mediterranean diet containing one medium potato/day has equivalent or non-different effects on risk factors for type 2 diabetes and heart disease compared to a healthy Mediterranean diet without potatoes in adults with prediabetes. Participants will be randomly assigned to one of the test diets and be asked to consume this diet for 12 weeks (84 days). Testing will be conducted at the beginning and end of the study.
Detailed description
This is a 12-week, 2-arm parallel, randomized controlled feeding trial. Participants will be randomized to either a Mediterranean-style diet that includes 1 medium potato/day/2000 kcal replacing some grains , or a traditional-style Mediterranean dietary pattern without potatoes. All food will be provided for the 12-week study duration.
Interventions
OTHERMediterranean-style diet with potatoes
The diet will contain 1 medium potato/day/2000 kcal
OTHERTraditional-style Mediterranean diet
Traditional-style Mediterranean diet higher in grains
Sponsors
Penn State University
Alliance for Potato Research & Education
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
25 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Age 25-65 years * Prediabetes assessed by an HbA1c of 5.7-6.4% or fasting glucose 100-125 mg/dL at screening * BMI 25-40 kg/m2 at screening
Exclusion criteria
* HbA1c ≥6.5% at screening * LDL-C (calculated with the Martin-Hopkins equation) ≥190 mg/dL at screening * Hemoglobin \<13.2 g/dL at screening * Fasting triglycerides \>350 mg/dL at screening -≥10% change in body weight within the 6 months prior to enrollment * Blood pressure \>140/90 mmHg at screening * Type 1 or type 2 diabetes * Prescription of anti-hypertensive, lipid-lowering, or glucose-lowering drugs * Intake of supplements that affect the outcomes of interest (i.e., lipid, blood pressure, or glucose lowering; vitamin C or multi-vitamins containing vitamin C) and are unwilling to cease during the study period. * History of liver, kidney, or autoimmune disease * Prior cardiovascular event (e.g., stroke, heart attack) * Current pregnancy or intention of pregnancy within the next 6 months * Lactation within the prior 6 months * Allergy/intolerance/sensitivity/dislike of any foods in the study menus * Antibiotic use within the prior 1 month * Oral steroid use within the prior 1 month * Use of tobacco or nicotine-containing products within the past 6 months * History of cancer at any site within the past 10 years (eligible if ≥10 years without recurrence) or non-melanoma skin cancer within the past 5 years (eligible if ≥5 years without recurrence) * Participation in another clinical trial within 60 days of baseline * Currently following a restricted or weight-loss diet * Prior bariatric surgery * Intake of \>14 alcoholic drinks/week and/or not willing to avoid alcohol consumption for 48 hours prior to test visits * Principal Investigator discretion related to the potential participant's ability to adhere to the study requirements, including being able to come to attend visits * Does not speak and/or understand English * Unwilling to refrain from donating blood during the study * Weight \<110 lb
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in HbA1c | 12-weeks | HbA1c will be assessed at baseline and 12-weeks and expressed as percentage . The change in HbA1c will be calculated by subtracting the baseline value from the 12 week value and expressed as percentage point change. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in fasting glucose | 12-weeks | Change in fasting plasma glucose expressed as mg/dL. Change in glucose will be calculated as the mean of the 12 week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in mean glucose | 12-weeks | Change in mean glucose assessed by a continuous glucose monitor (CGM) expressed as mg/dL. Change in mean glucose will be calculated as mean glucose assessed from 7 days of CGM wear at 12 weeks minus mean glucose assessed from 7 days of CGM wear at baseline. |
| Change in mean time in range | 12-weeks | Change in mean time in range (glucose 70-140 mg/dL) assessed by a continuous glucose monitor (CGM) expressed as minutes per day. Change in mean time in range will be calculated as mean time in range assessed from 7 days of CGM wear at 12 weeks minus mean time in range assessed from 7 days of CGM wear at baseline. |
| Change in glycemic variability | 12-weeks | Change in mean glycemic variability assessed by a continuous glucose monitor (CGM) expressed as the coefficient of variability. Change in mean glycemic variability will be calculated as mean glycemic variability assessed from 7 days of CGM wear at 12 weeks minus mean glycemic variability assessed from 7 days of CGM wear at baseline. |
| Change in fasting insulin | 12-weeks | Change in fasting serum insulin expressed as micro IU/mL. Change in insulin will be calculated as the mean of the 12 week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in homeostatic model of insulin resistance (HOMA-IR) | 12-weeks | Homeostatic model of insulin resistance (HOMA-IR) will be calculated from insulin and glucose measured from a fasting blood sample. Calculated as (insulin × glucose) / 22.5. Change in HOMA-IR will be calculated as the mean of the 12 week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in LDL-Cholesterol | 12-weeks | Assessed from fasting blood draw expressed in mg/dL. Change in LDL-cholesterol will be calculated as the mean of the 12-week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in apolipoprotein B | 12-weeks | Assessed from fasting blood draw expressed in mg/dL. Change in apolipoprotein B will be calculated by subtracting the baseline value from the 12 week value. |
| Change in non-HDL cholesterol | 12-weeks | Assessed from fasting blood draw expressed in mg/dL. Change in non-HDL cholesterol will be calculated as the mean of the 12-week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in Total Cholesterol | 12-weeks | Assessed from fasting blood draw expressed in mg/dL. Change in total cholesterol will be calculated as the mean of the 12-week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in HDL-Cholesterol | 12-weeks | Assessed from fasting blood draw expressed in mg/dL. Change in HDL-cholesterol will be calculated as the mean of the 12-week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in Triglycerides | 12-weeks | Assessed from fasting blood draw expressed in mg/dL. Change in triglycerides will be calculated as the mean of the 12-week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in C-reactive protein | 12-weeks | Assessed from fasting blood draw expressed in mg/L. Change in C-reactive protein will be calculated as the mean of the 12-week measures (i.e., mean of day 1 and day 2 values) minus the mean of the baseline measures (i.e., mean of day 1 and day 2 values). |
| Change in Central Systolic and Diastolic Blood Pressure | 12-weeks | Central blood pressure measured assessed using a SphymoCor Xcel (Atcor Medical) at baseline \& 12 weeks. Change will be calculated by subtracting the baseline value from the end point value. |
| Change in Peripheral Systolic and Diastolic Blood Pressure | 12-weeks | Peripheral blood pressure measured assessed using a SphymoCor Xcel (Atcor Medical) at baseline \& 12 weeks. Change will be calculated by subtracting the baseline value from the end point value. |
| Change in Carotid-Femoral Pulse Wave Velocity | 12-weeks | Measured assessed using a SphymoCor Xcel (Atcor Medical) at baseline \& 12 weeks. Change will be calculated by subtracting the baseline value from the end point value. |
| Change in particle size and number of LDL, HDL, triglyceride rich lipoproteins | 12-weeks | Measured via Nuclear Magnetic Resonance |
| Diet Satisfaction | 12-weeks | Participants will complete a survey that we have previously developed to assess diet satisfaction at 12 weeks. |
Contacts
CONTACTKristina Petersen, PhD
CONTACTStacey Meily
Outcome results
None listed