The Ability of Pecan Consumption to Improve Vascular Function and Reduce Chronic Disease Risk in Aging Adults
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Georgia
- Enrollment
- 50
- Locations
- 1
- Primary Endpoint
- Change in fasting and postprandial Flow-Mediated Dilation from baseline to 4 weeks
Study Overview
Brief Summary
Background: To date, there are no published studies on the effects of pecans on vascular function following a high-fat meal.
Purpose: To examine the impact of daily pecan consumption for a 4-week period on vascular health and other markers of cardiovascular disease risk in aging adults.
Detailed Description
This will be a randomized, controlled trial in men and postmenopausal women (50-75y). Subjects will be randomized into one of the two study groups: a control group (CON) following their usual diet, or intervention group (PECAN) following their usual diet but also consuming 68g/day of pecans as a snack.
There will be 3 visits: A Screening visit and a baseline and post-diet intervention visit (4-weeks). Anthropometrics, questionnaires, a fasting blood sample, and fasting vascular measures will be collected at each visit. Subjects will participate in a saturated fatty acid meal challenge in which additional blood, vascular measurements will be collected.
Hypothesis
Daily pecan consumption will result in improved fasting blood lipids, vascular measures, antioxidant status, and appetite compared to the control group. Additionally, also the PECAN group will result in improved postprandial blood lipids and vascular measures compared to the control group.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Prevention
- Masking
- None
Eligibility Criteria
- Ages
- 50 Years to 75 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Men and postmenopausal women (without menses for 1 yr and follicle stimulating hormone > 30 IU/mL) between the ages of 50-75y
- •Body mass indexes (BMI) between 18-34.9kg/m2
Exclusion Criteria
- •Nut consumption >2 servings/week or tree nut butter consumption >3 servings/week
- •Pre-menopausal and menopausal women, hormone replacement therapy if less than 2 years
- •Regularly exercise more than 3 h/week
- •Weight gain or loss more than 5% of their body weight in the past 3 months
- •Plans to begin a weight loss/exercise regimen during the trial
- •Gastrointestinal surgeries, conditions or disorders
- •History of medical or surgical events that could affect swallowing
- •Chronic or metabolic diseases
- •Previous MI, stroke, or cancer
- •Fasting blood glucose levels greater than 126 mg/dL
- •Blood pressure greater than 180/120 mmHg
- •Medication use affecting digestion and absorption, metabolism
- •Lipid-lowering medications
- •Medications for diabetes, depression, or ADD/ADHD
- •Regular use of medications known to affect endothelial function or blood vessel tone
- •Blood pressure medication and steroid/hormone therapies
- •Individuals on a medically prescribed or special diet
- •Individuals with food allergies to foods specifically in the study
- •Excessively use alcohol (greater than 3 drinks/d for men; greater than 2 drinks/d for women)
- •Tobacco or nicotine use
- •Individuals taking fish oil and omega-3 fatty acid supplements
- •Significant head trauma or brain surgery
- •A score >26 on the Beck's Depression Inventory II (BDI-II)
- •A score <24 on the Mini-Mental State Examination (MMSE) will be excluded.
Arms & Interventions
Control
Participants in this group avoid all nuts for 4-weeks
PECAN
Participants in this group consume 68 g of pecans/d with no other changes to their habitual diet and avoid all other nuts.
Intervention: PECAN (Dietary Supplement)
Outcomes
Primary Outcomes
Change in fasting and postprandial Flow-Mediated Dilation from baseline to 4 weeks
Time Frame: Baseline and 4 weeks
Flow-Mediated Dilation %
Change in fasting and postprandial vessel diameter from baseline to 4 weeks
Time Frame: Baseline and 4 weeks
baseline diameter (mm) and peak dilation (mm)
Change in fasting and postprandial reactive hyperemia velocity from baseline to 4 weeks
Time Frame: Baseline and 4 weeks
Baseline velocity (cm/s) and reactive hyperemia velocity (cm/s)
Change in fasting and postprandial shear rate from baseline to 4 weeks
Time Frame: Baseline and 4 weeks
baseline shear rate (sec.-1) and reactive hyperemia shear rate (sec.-1)
Change in fasting and postprandial Continuous-Wave Near-Infrared Spectrometry from baseline to 4 weeks
Time Frame: Baseline and 4 weeks
O2 desaturation rate (%.sec-1), and O2 resaturation rate (%.sec-1)
Secondary Outcomes
- Change in baseline total body fat percentage at 4 weeks(Baseline and 4 weeks)
- Change in baseline weight at 4 weeks(Baseline and 4 weeks)
- Change in fasting blood lipids from baseline to 4 weeks(Baseline and 4 weeks)
- Change in baseline waist and hip circumference(Baseline and 4 weeks)
- Change in fasting and postprandial hunger and satiety from baseline to 4 weeks(Baseline and 4 weeks)
- Change in blood pressure from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting and postprandial insulin from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting and postprandial antioxidants from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting and postprandial lipid peroxidation from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting inflammation from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting and postprandial glucose and triglycerides from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting and postprandial peptide YY, cholecystokinin (CCK), and ghrelin from baseline to 4 weeks(Baseline and 4 weeks)
- Change in fasting and postprandial non-esterified free fatty acids (NEFA) from baseline to 4 weeks(Baseline and 4 weeks)
Investigators
Jamie Cooper, PhD
Associate Professor, Dept. of Foods and Nutrition
University of Georgia