Peanuts for Cardiometabolic, Brain, and Intestinal Health

Impact of Peanuts on Cardiometabolic, Cognitive, and Intestinal Health in Prediabetes Among Racially Diverse Populations

The overall objective of this 14-month randomized crossover study is to seek evidence demonstrating that daily consumption of peanuts and peanut products improve cardiometabolic, cognitive, and intestinal health in a racially diverse prediabetes population.

Study Overview

• Status: Recruiting
• Conditions: Prediabetes; Cognition; Gut Microbiota; Adult; Microvascular Function; Arterial Stiffness, Blood Pressure; Endothelial Function (Reactive Hyperemia); Prediabetes (Insulin Resistance, Impaired Glucose Tolerance)
• Intervention / Treatment: Dietary supplement: Peanuts

Detailed Description

In the US, 37.1 million adults have diabetes mellitus and 96 million have prediabetes. Type 2 diabetes mellitus (T2DM) accounts for 95% of the cases and results in many public health complications that increase economic burden and reduce productivity and quality of life. Eight out of 10 people with T2DM die from cardiovascular disease, while those with T2DM also face a 50% higher risk of developing dementia compared to healthy individuals. Also, studies indicate that intestinal health significantly influences the development of T2DM. Of note, the burden of T2DM is particularly pronounced in non-Hispanic Black and Hispanic populations compared to the non-Hispanic White population. Prevention and treatment of T2DM focus on lifestyle changes including dietary modifications. Plant-based foods, including peanuts and peanut products, have been increasingly recognized for their importance in the prevention and management of prediabetes and T2DM due to their unique nutritional profile, including their favorable fatty acid composition, fiber content, and bioactive compounds. While emerging evidence indicates that peanut improves cardiometabolic, cognitive and intestinal health, no studies have collectively and comprehensively evaluated the effects of peanut or peanut product consumption on the cardiometabolic, cognitive, and intestinal health of individuals with prediabetes or T2DM. Thus, this study aims to investigate whether adults with prediabetes consuming 43 g of peanut butter (1 snack cup) 3 x/week, 42 g of dry roasted peanuts (1/3 of a cup) 3x/week, or 56 g of peanut flour 1x/week for six months will have 1) reduced levels of serum HbA1c, fasting glucose (FBG), insulin, HOMA-IR (homeostatic model assessment of insulin resistance) and improved lipid profile, 2) reduced blood pressure, improved endothelial function, arterial stiffness and microvascular function, 3) Improved gut microbiota composition and reduced intestinal permeability, 4) improved cognitive function (verbal memory and executive functions [inhibition, working memory, cognitive flexibility]) and brain health metrics as assessed by neuroimaging, and 5) reduced serum markers of oxidative stress and inflammation. The effectiveness of the intervention on the abovementioned outcomes among races including non-Hispanic Black (NHBA), non-Hispanic White (NHWA), non-Hispanic Asian (NHAA) and Hispanic (HA) adults will also be compared. Lastly, whether changes in cardiometabolic and cognitive outcomes are associated with changes in intestinal microbiota outcomes and whether changes in cardiometabolic outcomes are associated with changes in cognitive function parameters will be explored.

• Study Type: Interventional
• Enrollment (Estimated): 72
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Rafaela G Feresin, PhD; Phone Number: 404-413-1233; Email: peanuts@gsu.edu

Study Locations

• United States
  • Georgia
    • Atlanta, Georgia, United States, 30303
      • Recruiting
      • Georgia State University
      • Contact: Rafaela G Feresin, PhD; Phone Number: 404-413-1233; Email: peanuts@gsu.edu
      • Principal Investigator: Rafaela G Feresin, PhD
      • Sub-Investigator: Tricia Z King, PhD
      • Sub-Investigator: Brett J Wong, PhD
      • Sub-Investigator: Elizabeth L Tighe, PhD
      • Sub-Investigator: Andrew T Gewirtz, PhD
      • Sub-Investigator: Vince D Calhoun, PhD
      • Sub-Investigator: Puja K Mehta, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• men and women
• 20-59 years of age
• BMI: 24.5 - 35.5 kg/m^2
• Prediabetes (fasting blood glucose levels 100-125 mg/dL and/or HbA1c between 5.7-6.4%)
• Ability to give consent

Exclusion Criteria:

• Allergies to peanuts and peanut products
• Use of insulin, antidiabetic, antibiotics, and anti-inflammatory drugs
• Active cancer, gastrointestinal, renal, cardiovascular, thyroid, and neurological diseases or severe head injury
• Smoking
• Consumes greater than 2 alcoholic beverages per day
• Consumes antioxidant, probiotic, and prebiotic supplements
• Pregnant or Lactating
• Actively participating in a weight loss program

MRI Exclusion Criteria:

• Certain neurological disorders (e.g., uncontrolled seizure disorders)
• Braces on their teeth, a cardiac pacemaker; hearing aid; other metal in the body or eyes (which may include certain metallic-embedded tattoos), including but not limited to pins, screws, shrapnel, plates, dentures or other metal objects

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control; No intervention
Experimental: Peanut; 43 g of peanut butter (1snack cup) 3 x/week, 42 g of dry roasted peanuts (1/3 of a cup) 3x/week, or 56 g of peanut flour 1x/week for 6 months	Dietary supplement: Peanuts; 43 g of peanut butter (1 snack cup) 3 x/week, 42 g of dry roasted peanuts (1/3 of a cup) 3x/week, or 56 g of peanut flour 1x/week for 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Glucose	Measurement of fasting blood glucose	Baseline, 3 months, and 6 months
Glycosylated hemoglobin	Measurement of fasting glycosylated hemoglobin	Baseline, 3 months, and 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ambulatory Blood Pressure	Assessment of whole-day ambulatory blood pressure during daytime and nighttime periods.	Baseline, 3 months, and 6 months
Fasting Insulin	Measurement of fasting insulin	Baseline, 3 months, and 6 months
Homeostasis model assessment-insulin resistance (HOMA-R)	Calculated as fasting insulin (mU/mL) x fasting glucose (mg/dL)/405	Baseline, 3 months, and 6 months
Blood Lipid Profile	Measurement of blood lipid profile	Baseline, 3 months, and 6 months
Gut Microbiota Composition	Analysis of stool sample for determination of absolute levels of bacteria and relative species composition	Baseline, 3 months, and 6 months
Global Cognitive Ability	Measured using NIH Toolbox Picture Vocabulary test and Oral Reading Recognition	Baseline, 3 months, and 6 months
Performance Validity	Assessed using Rey 15	Baseline, 3 months, and 6 months
Verbal Memory & Recognition	Measured using Rey Auditory Verbal Learning Test with appropriate alternate forms	Baseline, 3 months, and 6 months
Cognitive Inhibition	Measured using Delis-Kaplan Executive Function System Color Word Interference, and NIH Toolbox Flanker Inhibitory Control and Attention	Baseline, 3 months, and 6 months
Cognitive Flexibility	Assessed using Delis-Kaplan Executive Function System Trails and Verbal Fluency Switching	Baseline, 3 months, and 6 months
Working Memory	Measured using Digit Span and NIH Toolbox List Sorting	Baseline, 3 months, and 6 months
Processing Speed	Measured using NIH Toolbox Pattern Comparison and Oral Symbol Digit tests	Baseline, 3 months, and 6 months
Associative Memory	Measured using NIH Toolbox Face Name Associative Memory Exam and Face Name Associative Memory Exam Delay tests	Baseline, 3 months, and 6 months
Attention	Assessed using Wechsler Adult Intelligence Scale - IV and Rey Auditory Verbal Learning Test Trial 1	Baseline, 3 months, and 6 months
Problem-Solving	Assessed using NIH Toolbox Visual Reasoning Test	Baseline, 3 months, and 6 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reactive Hyperemia Index	Assessment of endothelial function in response to increased shear stress using EndoPAT2000	Baseline, 3 months, and 6 months
Pulse Wave Velocity	Arterial Stiffness will be assessed by pulse wave velocity using SphygmCor	Baseline, 3 months, and 6 months
Percent Maximal Microvascular Blood Flow	Micro-vessel blood flow in response to local heating stimulus will be assessed using a Laser Doppler	Baseline, 3 months, and 6 months
Circulating Markers of Inflammation and Oxidative Stress	Measurement of concentrations of circulating markers of inflammation such as CRP and oxidative stress such as TBARS in blood plasma and serum samples	Baseline, 3 months, and 6 months
Urinary Polyphenolic Metabolites	24-hour urine collection samples will be assessed for polyphenol metabolites	Baseline, 3 months, and 6 months
Body Fat	DEXA will be used to assess body fat.	Baseline, 3 months, and 6 months
Spontaneous brain activity at rest	Assessed with resting state-functional Magnetic Resonance Imaging	Baseline and 6 months
Blood flow (perfusion) in the brain	Assessed with Arterial Spin Labeling Magnetic Resonance Imaging	Baseline and 6 months

Collaborators and Investigators

• Sponsor: Georgia State University
• Collaborators: United States Department of Agriculture (USDA); The Peanut Institute
• Investigators: Principal Investigator: Rafaela G Feresin, PhD, Georgia State University

Study record dates

Study Major Dates

• Study Start (Actual): March 6, 2025
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): September 1, 2027

Study Registration Dates

• First Submitted: March 4, 2025
• First Submitted That Met QC Criteria: March 4, 2025
• First Posted (Actual): March 10, 2025

Study Record Updates

• Last Update Posted (Actual): March 27, 2026
• Last Update Submitted That Met QC Criteria: March 23, 2026
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: neuroimaging; cognitive function; insulin resistance; vascular function; gut microbiota; prediabetes; endothelial function; microvascular function; peanuts; dietary intervention; cardiovascular health; type II diabetes; metabolic health; nuts; functional foods
• Additional Relevant MeSH Terms: Endocrine System Diseases; Vascular Diseases; Cardiovascular Diseases; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Hyperinsulinism; Hyperglycemia; Nutritional and Metabolic Diseases; Diabetes Mellitus, Type 2; Insulin Resistance; Prediabetic State; Glucose Intolerance; Hyperemia
• Other Study ID Numbers: H25014

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No