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Completed

NCT Number: NCT04385537

The Ability of Pecan Consumption to Improve Vascular Function and Reduce Chronic Disease Risk in Aging Adults

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.

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Key information

Conditions

Aging

Age range

50 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of Georgia- Department of Foods and Nutrition

Athens, Georgia, 30605, United States

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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.

Treatment and study plan

PECAN

Dietary Supplement

Raw pecan halves without other changes to their habitual diet.

Primary outcomes

  1. Change in fasting and postprandial Flow-Mediated Dilation from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Flow-Mediated Dilation %

  2. 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)

  3. 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)

  4. 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)

  5. 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

  1. Change in fasting blood lipids from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Total cholesterol (mg/dL), high-density lipoprotein (HDL) cholesterol (mg/dL), triglycerides (mg/dL), low-density lipoprotein (LDL) cholesterol (mg/dL), apolipoprotein B (mg/dL)

  2. Change in baseline weight at 4 weeks

    Time frame: Baseline and 4 weeks

    weight (kg)

  3. Change in baseline waist and hip circumference

    Time frame: Baseline and 4 weeks

    waist and hip circumference (cm)

  4. Change in blood pressure from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Systolic and Diastolic Blood Pressure (mm Hg)

  5. Change in baseline total body fat percentage at 4 weeks

    Time frame: Baseline and 4 weeks

    total body fat percentage (%)

  6. Change in fasting and postprandial insulin from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Insulin (uU/mL)

  7. Change in fasting and postprandial antioxidants from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Total antioxidant capacity (uM trolox equivalents) measured via Oxygen Radical Absorbance Capacity (ORAC)

  8. Change in fasting and postprandial lipid peroxidation from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Malondialdehyde (MDA) (uM) measured via Thiobarbituric acid reactive substances (TBARS) assay.

  9. Change in fasting inflammation from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Interleukin-6 (pg/mL), C-reactive Protein (pg/mL), Tumor Necrosis Factor-α (pg/mL), Plasminogen Activator-1 (pg/mL)

  10. Change in fasting and postprandial glucose and triglycerides from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Glucose (mg/dL) and triglycerides (mg/dL)

  11. Change in fasting and postprandial peptide YY, cholecystokinin (CCK), and ghrelin from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Peptide YY (pg/mL), CCK (pg/mL), ghrelin (pg/mL)

  12. Change in fasting and postprandial non-esterified free fatty acids (NEFA) from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    NEFA (mEq/L)

  13. Change in fasting and postprandial hunger and satiety from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    Hunger, fullness, prospective consumption, and desire to eat measured via a Visual Analog Scale (VAS) (mm). The range of scores on the continuous VAS is between 0mm (no hunger, fullness, prospective consumption and desire to eat) and 100mm (the greatest feeling of hunger, fullness, prospective consumption and desire to eat)

Other outcomes

  1. Change in fasting and postprandial composite cognitive function from baseline to 4 weeks

    Time frame: Baseline and 4 weeks. Measured at fasting, and 30 minutes and 3.5 hours postprandial.

    NIH tool box- Cognitive Battery (NIHTB-CB) computed- theta score for the sum of all subtests

  2. Change in fasting and postprandial Cognitive Battery Motivation from baseline to 4 weeks

    Time frame: Baseline and 4 weeks. Measured at fasting, and 30 minutes and 3.5 hours postprandial.

    Visual Analogue Scale (VAS) (mm). This continuous scale is anchored by either no motivation (0mm) or extremely motivated (100mm).

  3. Change in fasting and postprandial NIHTB-CB Flanker Inhibitory Control and Attention Test, and Dimensional Change Card Sort Test from baseline to 4 weeks

    Time frame: Baseline and 4 weeks. Measured at fasting, and 30 minutes and 3.5 hours postprandial.

    NIHTB-CB computed scores ranging from 0-10; high score representing greater accuracy

  4. Change in fasting and postprandial NIHTB-CB Auditory Learning Test, Picture Sequence Memory Task and List Sorting Working Memory Test from baseline to 4 weeks

    Time frame: Baseline and 4 weeks. Measured at fasting, and 30 minutes and 3.5 hours postprandial.

    NIHTB-CB computed scores representing the number of correctly recalled items; higher scores indicating better memory.

  5. Change in Pittsburg Sleep Quality Index scores from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    The scoring is out of 21 points, where a high score indicates poor sleep quality.

  6. Change in State Trait Anxiety Inventory scores from baseline to 4 weeks

    Time frame: Baseline and 4 weeks

    The scoring is out of 80 points, where high score indicates higher levels of anxiety.

Sponsors and collaborators

Lead sponsor

University of Georgia

Other

Collaborators

  • American Pecan Council

Registry information

Important dates

Study start
2020
Primary completion
2022
Study completion
2022
First posted
May 13, 2020
Registry last updated
May 24, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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