Pistachio Snacking and Metabolic Flexibility

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.

NCT Number	NCT07340125
Lead Sponsor	University of South Carolina Collaborators: American Pistachio Growers
Conditions	Overweight (BMI > 25), Obese But Otherwise Healthy Participants, Overweight or Obese, Obese Patients (BMI ≥ 30 kg/m²), Poor Sleep Quality, Healthy Participants, Physically Inactive
Enrollment	60 participants
Start Date	2025-09-01
Primary Completion	2026-08-01 (estimated)
Study Completion	2026-12-31 (estimated)
Updated on ClinicalTrials.gov	2026-01-14