Recruiting

Pistachio Snacking

Sponsor:

University of South Carolina

Code:

NCT07340125

Conditions

Overweight (BMI > 25)

Obese But Otherwise Healthy Participants

Overweight or Obese

Obese Patients (BMI ≥ 30 kg/m²)

Poor Sleep Quality

Eligibility Criteria

Sex: All

Age: 25 - 45

Healthy Volunteers: Accepted

Interventions

Pistachio

Study Details

Brief summary:

The purpose of this study is to evaluate the effects of pistachio snacking on metabolic flexibility (at rest, during exercise, and in post-exercise recovery) in healthy overweight and obese adults. Secondary goals include evaluating effects on changes in diet quality, sleep characteristics, physical activity, and hormonal health in women. In randomized order, participants will complete four days of pistachio snacking and four days of normal dietary habits (control). For both conditions, primary outcomes of resting substrate metabolism, metabolic flexibility during exercise, and post-exercise substrate metabolism will be measured pre-post intervention via indirect calorimetry. Secondary outcome of diet quality (kcal, carb, fat, protein) will be measured pre-post intervention via diet log. Exploratory outcomes of daily physical activity (steps, intensity), nightly sleep characteristics (quantity, quality, latency, efficiency), and daytime sleepiness and hunger.

Conditions

Overweight (BMI > 25)

Obese But Otherwise Healthy Participants

Overweight or Obese

Obese Patients (BMI ≥ 30 kg/m²)

Poor Sleep Quality

Study ID

NCT07340125

Start date

Sep 1, 2025

Status verified date

Jan, 2026

Completion date

Dec 31, 2026

Anticipated

Primary completion date

Aug 1, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 25 - 45

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Males and Females
  • Age: 25-45 years
  • Overweight or obese (BMI=25.0-34.9 kg/m²)
  • Poor sleep quality (Pittsburgh Sleep Quality Index ≥ 5)
  • Healthy (no diagnosed metabolic, cardiovascular, sleep, or other health condition that may significantly alter metabolism, sleep, or ability to participate in the exercise test)
  • Not meeting weekly physical activity recommendations (<150 min moderate-intensity exercise, <75 minutes of vigorous-intensity exercise, and <2 days of strength training)
  • Not following a diet that is restrictive or eliminates certain food group/types

Exclusion Criteria:

  • Allergies to nuts, especially tree nuts
  • Has a pacemaker
  • Following a diet that is restrictive or eliminates certain food group/types
  • Self-repoted health or disease state that may influence study outcomes, including known metabolic or endocrine disorder (e.g. prediabetes, type 1 or type 2 diabetes, or polycystic ovary syndrome), cardiovascular diseases, neuromuscular disorders, musculoskeletal disorders; current or recent history of cancer/cancer treatment (within the past year)
  • History of gastrointestinal surgery, hysterectomy
  • For women: pregnant or thinking of becoming pregnant during the time of participation, pregnant within the last year, currently breastfeeding, or known to be perimenopausal

Study Design

Enrollment

60 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Pistachio

Four days of pistachio snacking, to be consumed mid-morning (1oz; 9-11am), mid-afternoon (1oz; 2-4pm), and pre-sleep (0.5 oz; within 1hr of bedtime), while otherwise maintaining normal dietary habits. An addition snack will be consumed post-exercise (0.5oz).

no intervention: Control

Maintain normal dietary habits for four days.

Interventions

Pistachio

Roasted, lightly salted, pistachio kernels (no shell)

Primary outcome measure

  • resting metabolism [ Time Frame: Day 0 and Day 5 ]
  • exercise metabolic flexibility [ Time Frame: Day 0 and Day 5 ]
  • post-exercise metabolism [ Time Frame: Day 0 and Day 5 ]

Central Contacts and Locations

Central contacts

Callie Unrein, MS

803-777-5478sustainlab@mailbox.sc.edu

Locations

Public Health Research Center: Clinical Exercise Research Center

Recruiting

Columbia, South Carolina, United States, 29208

More Information

Sponsor

University of South Carolina

Last update posted

Jan 14, 2026

Last verified

Jan, 2026

Keywords

  • Pistachio
  • Tree Nuts
  • metabolic flexibility
  • metabolism
  • diet quality
  • snacking

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-09. This information was provided to ClinicalTrials.gov by University of South Carolina on 2026-01-14. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.