Type 2 Diabetes, Cardiovascular Diseases
Conditions
Brief summary
A two-period randomized crossover study will be conducted to evaluate the effect of nighttime pistachio consumption (i.e., after dinner and before sleep) on fasting blood sugar levels, longer-term blood sugar control, and risk factors for heart disease. This study will also investigate how pistachios affects gut health.
Detailed description
A two-period randomized crossover trial will be conducted. Participants will be randomized to receive each treatment for 12 weeks followed by a minimum 4-week wash-out period. During the pistachio treatment, participants will consume two ounces per day (57 g) of pistachios as an evening snack. During the control phase subjects will be given advice to consume 1-2 exchanges of carbohydrate as an evening snack, which is consistent with usual care. Markers of glycemic control, cardiovascular risk factors and gut health will be assessed at the beginning and the end of each treatment period.
Interventions
DRUGPistachio
Unsalted pistachios
OTHERUsual care
Advice and resources will be provided
Sponsors
Penn State University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
DOUBLE (Investigator, Outcomes Assessor)
Intervention model description
Crossover assignment
Eligibility
Sex/Gender
ALL
Age
30 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* BMI ≥25 and ≤45 kg/m2 * Fasting plasma glucose 100 - 125 mg/dL * non-Smoking
Exclusion criteria
* Diagnosed diabetes or fasting glucose \>126 mg/dl * Systolic blood pressure \>160mmHg or diastolic blood pressure \>100mmHg) * Prescribed anti-hypertensive, lipid lowering or glucose lowering drugs * Established cardiovascular disease, stroke, diabetes, liver, kidney or autoimmune disease or inflammatory conditions * Use of supplements (psyllium, fish oil, soy lecithin, phytoestrogens) and botanicals and not willing to cease for the duration of the study * Women who are pregnant, lactating, planning to become pregnant or have given birth in the past year * Weight loss of \>=10% of body weight within the 6 months prior to enrolling in the study * Smoking or use of any tobacco products * Allergy/intolerance/sensitive to pistachios * Consumption of \>14 alcoholic drinks/week * Shift-workers and those who cannot consume a snack in the evening
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Fasting plasma glucose concentration | 12 weeks | Fasting blood glucose (mg/dL) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Serum insulin concentration (mIU/L) | 12 weeks | fasting serum insulin levels assessed by blood draw |
| Peripheral systolic and diastolic blood pressure (mm Hg) | 12 weeks | Blood pressure measured assessed using a SphymoCor Xcel (Atcor Medical). |
| Central systolic and diastolic blood pressure (mm Hg) | 12 weeks | Blood pressure measured assessed using a SphymoCor Xcel (Atcor Medical). |
| Carotid-femoral pulse wave velocity (m/s) | 12 weeks | A measure of arterial stiffness assessed using a SphymoCor Xcel (Atcor Medical). A higher percentage value is indicative of greater arterial stiffness. |
| HOMA-IR | 12 weeks | Assessed using fasting blood draw and standardized HOMA-IR calculation. Fasting plasma glucose multiplied by fasting plasma insulin divided by 405. |
| Augmentation Index (%) | 12 weeks | A measure of arterial stiffness assessed using a SphymoCor Xcel (Atcor Medical). A higher percentage value is indicative of greater arterial stiffness. |
| LDL cholesterol concentration (mg/dL) | 12 weeks | Assessed using fasting blood draw |
| HbA1c | 12 weeks | HbA1c (%) will be assessed at the beginning and end of each treatment period |
| Total cholesterol concentration | 12 weeks | Assessed using fasting blood draw |
| Triglyceride concentration | 12 weeks | Assessed using fasting blood draw |
| waist circumference (cm) | 12 weeks | Measured 10 cm above the navel |
| body weight (lbs) | 12 weeks | Assessed using calibrated scale in Clinical Research Center |
| Diet quality: Healthy Eating Index 2015 | 12 weeks | Assessed using the Healthy Eating Index 2015 |
| Change in the composition of the gut microbiome | 12 weeks | microbiome composition assessed using fecal collection kit |
| HDL cholesterol concentration | 12 weeks | Assessed using fasting blood draw |
Countries
United States
Outcome results
None listed