MedPath

Pistachios Blood Sugar Control, Heart and Gut Health

Phase 2
Completed
Conditions
Cardiovascular Diseases
Type 2 Diabetes
Interventions
Other: Usual care
Registration Number
NCT04056208
Lead Sponsor
Penn State University
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.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
66
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

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Usual careUsual careAdvice to consume a snack that contains 1-2 exchanges (15-30 g of carbohydrate) as an evening snack - this is consistent with the current standard of care for people with impaired fasting glucose.
Evening Pistachio ConsumptionPistachioParticipants will consume two ounces per day (57 g) of pistachios as an evening snack (i.e., after dinner and before sleep).
Primary Outcome Measures
NameTimeMethod
Fasting plasma glucose concentration12 weeks

Fasting blood glucose (mg/dL)

Secondary Outcome Measures
NameTimeMethod
Central systolic and diastolic blood pressure (mm Hg)12 weeks

Blood pressure measured assessed using a SphymoCor Xcel (Atcor Medical).

Peripheral systolic and diastolic blood pressure (mm Hg)12 weeks

Blood pressure measured assessed using a SphymoCor Xcel (Atcor Medical).

Serum insulin concentration (mIU/L)12 weeks

fasting serum insulin levels assessed by blood draw

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.

body weight (lbs)12 weeks

Assessed using calibrated scale in Clinical Research Center

Diet quality: Healthy Eating Index 201512 weeks

Assessed using the Healthy Eating Index 2015

Change in the composition of the gut microbiome12 weeks

microbiome composition assessed using fecal collection kit

waist circumference (cm)12 weeks

Measured 10 cm above the navel

HDL cholesterol concentration12 weeks

Assessed using fasting blood draw

Total cholesterol concentration12 weeks

Assessed using fasting blood draw

Triglyceride concentration12 weeks

Assessed using fasting blood draw

HbA1c12 weeks

HbA1c (%) will be assessed at the beginning and end of each treatment period

LDL cholesterol concentration (mg/dL)12 weeks

Assessed using fasting blood draw

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.

HOMA-IR12 weeks

Assessed using fasting blood draw and standardized HOMA-IR calculation. Fasting plasma glucose multiplied by fasting plasma insulin divided by 405.

Trial Locations

Locations (1)

Pennsylvania State University

🇺🇸

University Park, Pennsylvania, United States

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