Pecan Consumption and Cognitive Function

Cognitive Function in Response to a Pecan-Enriched Meal

Human cognitive function is affected by age-related changes, with some areas beginning to decline in mid-adulthood and worsening with age. However, there is evidence that dietary interventions or the incorporation of certain healthy foods or nutrients, into the diet can have protective effects against cognitive decline. These foods include nutrients such as polyunsaturated fats, vitamins E and C, and polyphenols. Pecans are a rich source of polyunsaturated fatty acids, antioxidants (including polyphenols), and vitamin E. Pecans contain more total phenols than any other tree nut suggesting that they may be an ideal bioactive food to enhance cognitive performance; however, the relationship between pecan consumption and cognitive functioning has never been assessed. The overall goal behind this research is to determine the relationship between antioxidant-rich pecans and cognitive functioning in a postprandial state.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Other: Pecan Breakfast Shake; Other: Cream Breakfast Shake

Detailed Description

This trial will be a double-blinded, randomized, cross-over design in humans. There will be two study visits for two different test meals administered in random order. The two testing visits (v1 and v2) include blood draws and repetitions of the cognitive battery after consuming one of the two different test meals containing 1% milk, Nesquik, and either: 1) pecans, or 2) heavy whipping cream. There will be a 6-8 day washout period between each study visit.

Hypothesis: Investigators hypothesize that the pecan-enriched meal will 1.) improve performance on select measures of postprandial cognitive functioning (such as executive functioning, memory, learning, attention, and processing speed) 2.) improve postprandial markers of glycemic control, inflammation, antioxidant capacity, coagulation potential, and 3.) present a similar suppression of subjective appetite compared to the isocaloric, control meal that does not contain pecans.

• Study Type: Interventional
• Enrollment (Actual): 31
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Georgia
    • Athens, Georgia, United States, 30605
      • University of Georgia- Department of Foods and Nutrition

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 30 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18 to 30-years-old
• Healthy individuals
• Men and Women
• Normal body mass index (BMI) (18.5-24.9kg/m2). If BMI is 25 or greater, subjects can still qualify if their body fat percentage falls within healthy ranges defined as Men: 5-20%, and Women: 15-30% [22]
• Individuals with normal or corrected to normal vision
• Low-risk alcohol use as assessed by the AUDIT questionnaire (need a score of 7 or lower)
• No or minimal depression symptoms as indicated by the Beck's Depression Inventory (need a score of 9 or lower)
• Cognitive competence for education level and age as measured by the Mini-Mental State Examination (need a score of 26 or higher)

Exclusion Criteria:

• All chronic diseases (including, but not limited to, renal or bowel diseases, cardiovascular disease, and any form of diabetes)
• Known neurological, cognitive, or psychiatric conditions (including, but not limited to, mood disorders, anxiety disorders, and depression)
• Prescription medication use (with the exception of female contraception methods)
• Dietary supplement use (including, but not limited to, multivitamins and fish oil supplements)
• Alcohol intake >3 drinks/d for males or >2 drinks/d for females
• Diagnosis of ADHD or a learning difficulty (including, but not limited to, dyslexia)
• History of head injury (defined as loss of consciousness more than 10 minutes)
• History of inflammatory disorders (including, but not limited to, migraines, stroke, hypertension, hypercoagulation, vascular disease, thyroid conditions, blood disorders, coagulation disorders)
• Food allergies/sensitivities to foods provided in this protocol including tree nuts, gluten, and or lactose/dairy
• Regular consumption of nuts and/or nut butters defined as consumption of >2 servings (60g) of tree nuts or nut butters (e.g., peanut butter, almond butter) per week
• High caffeine consumption, defined as >400mg/d
• Individuals adhering to special diets (including, but not limited to, the ketogenic diet, intermittent fasting, Atkins diet, vegan diet, vegetarian diet, or carbohydrate-restricted diets)
• Illicit drug use
• Smoking or use of tobacco products
• Color-blindness
• History of current renal or bowel disease
• Females who are currently pregnant or lactating
• Active individuals (defined as performing >5 hours/week of scheduled exercise)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pecan Breakfast Shake; Participants will be given a breakfast shake consisting primarily of pecans, and 1% milk.	Other: Pecan Breakfast Shake; The pecan breakfast shake contains 68 grams of blended raw pecans. Participants will consume this shake at either visit 1 or visit 2 depending on randomization procedures.
Active Comparator: Cream Breakfast Shake; Participants will be given a breakfast shake consisting primarily of heavy whipping cream.	Other: Cream Breakfast Shake; The cream breakfast shake contains 138 grams of heavy whipping cream. Participants will consume this shake at either visit 1 or visit 2 depending on randomization procedures.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Alphabetic Working Memory, Choice Reaction Time, Digit Vigilance, N-back test, Word Recognition, Rapid Visual Information Processing, Picture Recognition, Immediate Word Recall, and Delayed Word Recall	Measured by Computerized Mental Performance Assessment System (COMPASS) computed scores of percent accuracy (total overall target stimuli/novel stimuli) Brain, Performance, and Nutrition Research Centre, Northumbria University	Change from baseline to 4 hours postprandially
Change in Serial Subtractions, Immediate Word Recall, and Delayed Word Recall.	Measured by Computerized Mental Performance Assessment System (COMPASS) computed scores of the number of responses (total correct responses/error responses) Brain, Performance, and Nutrition Research Centre, Northumbria University	Change from baseline to 4 hours postprandially
Change in Alphabetic Working Memory, Choice Reaction Time, Digit Vigilance, N-back, Picture Recognition, Rapid Visual Information Processing, Word Recognition.	Measured by Computerized Mental Performance Assessment System (COMPASS) computed scores of reaction time (msec) (overall, correct response, target stimuli, novel stimuli, number of false alarms, and number of missed sequences) Brain, Performance, and Nutrition Research Centre, Northumbria University	Change from baseline to 4 hours postprandially

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in glucose and triglycerides	Blood samples will be collected to measure Glucose (mg/dL), Triglycerides (mg/dL)	Change from baseline to 4 hours postprandially
Change in physiologic measures of appetite	Blood samples will be collected to measure Peptide YY (PYY) (pg/mL), Cholecystokinin (CCK) (pg/mL), Ghrelin (pg/mL), Glucagon-like Peptide 1 (GLP-1) (pg/mL), Gastric Inhibitory Peptide (GIP) (pg/mL), pancreatic peptide (PP) (pg/mL).	Change from baseline to 4 hours postprandially
Change in lipid peroxidation	Malondialdehyde (MDA) (uM) measured via Thiobarbituric acid reactive substances (TBARS) assay.	Change from baseline to 4 hours postprandially
Change in insulin	Insulin (uU/mL)	Change from baseline to 4 hours postprandially
Change in non-esterified free fatty acids (NEFA)	NEFA (mEq/L)	Change from baseline to 4 hours postprandially
Change in angiopoietin-like proteins-3 (ANGPTL3), angiopoietin-like-4 (ANGPTL4), and angiopoietin-like-8 (ANGPTL8)	ANGPTL-3 (pg/mL), ANGPTL-4 (pg/mL), ANGPTL-8 (pg/mL)	Change from baseline to 4 hours postprandially
Change in subjective measures of appetite	Appetite Visual Analog Scale (VAS) (mm). The range of scores on the continuous VAS is 0-100 mm. Zero represents no hunger, fullness, prospective consumption, and desire to eat, while 100 represents the greatest feeling of these outcomes.	Change from baseline to 4 hours postprandially. Also measured every hour for 10 hours after subject leaves the lab.
Change in total antioxidant capacity	Total antioxidant capacity (uM trolox equivalents) measured via Oxygen Radical Absorbance Capacity (ORAC) assay.	Change from baseline to 4 hours postprandially
Change in oxidized low density lipoprotein (LDL)	Oxidized Low-Density Lipoprotein (ox-LDL) (mg/dL)	Change from baseline to 4 hours postprandially

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in subjective measures of motivation	Motivation Visual Analog Scale (VAS) (mm). The range of scores on the continuous VAS is 0-100 mm. Zero represents no motivation while 100 represents the greatest feeling of this outcome.	Change from baseline to 4 hours postprandially
Change in subjective measures of alertness, stress, and tranquility	Computerized Mental Performance Assessment System (COMPASS) - Brain, Performance, and Nutrition Research Centre, Northumbria University. Visual Analogue Mood Scales (VAMS) (mm). The range of scores on the continuous VAS is 0-100 mm. Zero represents lesser feeling of alertness, stress, and tranquility, while 100 represents the greatest feeling of these outcomes.	Change from baseline to 4 hours postprandially
Change in subjective degree of sleepiness	Stanford Sleepiness Scale, in which the scale is rated from 1 to 7. A rating of 1 indicates feelings of being wide awake/alert/vital/active and a rating of 7 indicates the greatest feelings of sleepiness.	Change from baseline to 4 hours postprandially

Collaborators and Investigators

• Sponsor: University of Georgia
• Investigators: Principal Investigator: Jamie A Cooper, PhD, University of Georgia

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2021
• Primary Completion (Actual): February 25, 2023
• Study Completion (Actual): February 25, 2023

Study Registration Dates

• First Submitted: January 22, 2022
• First Submitted That Met QC Criteria: February 7, 2022
• First Posted (Actual): February 8, 2022

Study Record Updates

• Last Update Posted (Actual): April 14, 2023
• Last Update Submitted That Met QC Criteria: April 12, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: PROJECT00004889

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The plan is to share group averages through publication.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No