Pistachio Intake and Nutrition-Related Outcomes in Individuals on GLP-1 Therapy

Dietary Pistachio Intake and Nutrition-Related Outcomes in Individuals Using GLP-1 Receptor Agonists: A Randomized Controlled Trial

In this study will look at how eating pistachios every day might affect participants weight, how healthy their diet is, and how they feel when eating. Investigators want to see if adding pistachios to meals for 12 weeks helps participants feel fuller, have more energy, and improve body composition. The study will include adults who have been taking GLP-1 medicines like semaglutide or tirzepatide for at least three months. Investigators also want to see if eating pistachios improves overall diet quality and health markers like tiredness and certain levels in blood.

Study Overview

• Status: Recruiting
• Conditions: Obesity & Overweight; Food Acceptance; Dietary Change
• Intervention / Treatment: Procedure: Dual-energy X-ray absorptiometry (DEXA) scans; Dietary supplement: Pistachios

• Study Type: Interventional
• Enrollment (Estimated): 108
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ian Neeland, MD; Phone Number: 216-844-5965; Email: Ian.Neeland@UHhospitals.org
• Study Contact Backup: Name: Abigail Raffner, PhD, RD, LD; Phone Number: 216-368-0756; Email: Abigail.Raffner@UHhospitals.org

Study Locations

• United States
  • Ohio
    • Clevland, Ohio, United States, 44106
      • Recruiting
      • University Hospitals Cleveland Medical Center
      • Contact: Ian Neeland, MD; Phone Number: 216-844-5965; Email: Ian.Neeland@UHhospitals.org
      • Contact: Abigail Raffner, PhD, RD, LD; Phone Number: 216-368-0756; Email: Abigail.Raffner@UHhospitals.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Individuals with a BMI ≥30 kg/m2 or with a BMI ≥27 kg/m2 with at least one weight-related comorbidity who have been continuously using semaglutide or tirzepatide for three months for a clinical indication and remain on the therapy at the time of enrollment

Exclusion Criteria:

• No use or contraindication to use of a GLP-1 RA
• Known allergy to nuts
• Pregnant or breastfeeding
• Incarcerated

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pistachio Group; Participants in this group will eat 2 ounces, or 53 grams of dry-roasted, unsalted pistachios each day along with their regular diet.	Procedure: Dual-energy X-ray absorptiometry (DEXA) scans; DEXA scans will be used to measure body fat; Dietary supplement: Pistachios; Participants will eat 2 ounces, or about 53 grams, of dry-roasted, unsalted pistachios each day along with their regular diet
Active Comparator: No Pistachio Group; Participants in this group will continue eating regular diet without pistachios.	Procedure: Dual-energy X-ray absorptiometry (DEXA) scans; DEXA scans will be used to measure body fat

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change is Satiety as measured by the Hunger and Satiety Visual Analog Scales (VAS)	Participants will rate their perceived hunger, fullness, and desire to eat on a 100-mm scale, with endpoints ranging from "not at all" to "extremely" for each category.	Baseline, End of study (12 weeks)
Change in fatigue as measured by the Fatigue Severity VAS-F Survey	Each item is presented on a 100-mm scale, with endpoints labeled to reflect the extremes of the sensation being measured (e.g., "Not at all tired" to "Extremely tired"). Participants will complete the VAS-F at consistent times of the day to minimize variability. Scores will be recorded both before and after meals to capture potential fluctuations in energy levels.	Baseline, End of study (12 weeks)
Change in mood/well-being as measured by the Mental clarity, energy levels, and motivation VAS.	Each item is presented on a 100-mm scale, with endpoints labeled to reflect the extremes of being measured ranging from, for example, "not at all" to "extremely".	Baseline, End of study (12 weeks)
Change in dietary quality as measured by Healthy Eating Index (HEI)	HEI scores measure how well a diet aligns with the Dietary Guidelines for Americans. The scores range from 0 to 100, with higher scores indicating foods align with key dietary recommendations and dietary patterns published in the Dietary Guidelines.	Baseline, End of study (12 weeks)
Change in fasting glucose as measured by medical record review		Baseline, End of study (12 weeks)
Change in HbA1c as measured by medical record review		Baseline, End of study (12 weeks)
Change in total cholesterol as measured by medical record review		Baseline, End of study (12 weeks)
Change in LDL-C as measured by medical record review		Baseline, End of study (12 weeks)
Change in HDL-C as measured by medical record review		Baseline, End of study (12 weeks)
Change in triglycerides as measured by medical record review		Baseline, End of study (12 weeks)
Change in food enjoyment as measured by the Food Pleasure Scale (FPS)	The FPS is a validated 21-item tool designed to measure multiple dimensions of food-related enjoyment, including sensory characteristics (appearance, odor, taste, texture), expectations and desires (memories, habits, expectations, choices, needs), and other relevant factors. The importance of each item in relation to general pleasurable experiences of food is rated on a 5-point ordinal scale ranging from 1 ("Not important at all") to 5 ("Extremely important").	Baseline, End of study (12 weeks)
Change in physical activity as measured by International Physical Activity Questionnaire (IPAQ)	The IPAQ short form consists of 7 questions designed to assess physical activity levels over the past 7 days in adults. The score is calculated using published guidelines and ranges from 0 to infinity and measures physical activity in median median MET-minutes/week. This is a continuous measure and is calculated as: Total MET-min/week = (Walk METs*min*days) + (Moderate activity METs*min*days) + Vigorous activity METs*min*days).	Baseline, End of study (12 weeks)

Secondary Outcome Measures

Outcome Measure	Time Frame
Change in body weight as measured by medical record review	Baseline, End of study (12 weeks)
Change in waist circumference as measured by medical record review	Baseline, End of study (12 weeks)
Change in hip circumference as measured by medical record review	Baseline, End of study (12 weeks)
Change in fat mass as measured by DEXA scan	Baseline, End of study (12 weeks)
Change in lean body mass as measured by DEXA scan	Baseline, End of study (12 weeks)
Change in overall body fat percentage as measured by DEXA scan	Baseline, End of study (12 weeks)

Collaborators and Investigators

• Sponsor: Ian J. Neeland, MD
• Investigators: Principal Investigator: Ian Neeland, MD, University Hospitals Cleveland Medical Center; Principal Investigator: Abigail Raffner, MD, University Hospitals Cleveland Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): January 29, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: November 17, 2025
• First Submitted That Met QC Criteria: November 17, 2025
• First Posted (Actual): November 24, 2025

Study Record Updates

• Last Update Posted (Actual): February 20, 2026
• Last Update Submitted That Met QC Criteria: February 17, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Satiety; Dietary quality; Eating enjoyment; Weight-related outcomes
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity; Investigative Techniques; Diagnostic Techniques and Procedures; Diagnosis; Diagnostic Imaging; Chemistry Techniques, Analytical; Radiography; Densitometry; Photometry; Absorptiometry, Photon
• Other Study ID Numbers: STUDY20250409

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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