Disrupting the vicious cycle: Effects of Montmorency tart cherry supplementation on sleep and inflammation among individuals with overweight and obesity

 This randomized, double-blind, crossover study evaluated whether a commonly used dose of US Montmorency tart cherry (MTC) powder improves sleep and inflammation outcomes in adults with overweight or obesity who experience sleep issues. Thirty-four participants with a mean body mass index of 32.1 ± 7.0 kg/m2 were enrolled and randomized to receive either MTC capsules (500 mg) or a placebo taken one hour before bedtime for 14 days, with a washout period of at least 10 days between arms. Objective sleep measures included total sleep time, durations of deep and REM sleep, nap duration, and nocturnal sleep duration assessed using the Zmachine device and the Fitbit Inspire 3; Zmachine data were collected for three consecutive days before and after each intervention arm, and comparable Fitbit data were analyzed for the same timeframes.

Subjective sleep assessments were collected at baseline and follow-up for each arm using validated instruments: the Pittsburgh Sleep Quality Index (PSQI), the Sleep Quality Scale (SQS), and the Insomnia Severity Index (ISI). Inflammatory biomarkers measured from blood samples included C-reactive protein (CRP) and a panel of cytokines: TNF-α, IL-6, IL-8, IL-10, and IL-17A. The investigators report that no significant effects of MTC supplementation were observed for any of the measured sleep or inflammation outcomes (p > 0.05 for all comparisons). Based on these null findings at the tested dose, the authors conclude that studies in individuals with overweight and obesity should evaluate higher MTC doses than those currently recommended to determine whether a dose-dependent effect exists in this population. The publication also notes that the authors declared no conflicts of interest and that the funders had no role in study design, data collection, analysis, interpretation, manuscript preparation, or publication decisions.

This trial contributes rigorous randomized crossover evidence using both objective device-based sleep assessment and subjective sleep questionnaires alongside inflammatory biomarker analyses, specifically addressing a gap in prior research by focusing on individuals with overweight and obesity. The study’s methods—short-term nightly dosing, crossover design, layered objective and subjective sleep measures, and cytokine panels—provide a clear framework for future research to test alternative dosing strategies, longer treatment durations, or different formulations of tart cherry supplementation in populations at elevated cardiometabolic and inflammation-related risk.