TY  - JOUR
AU  - Sinclair, Jonathan K
AU  - Baker, Lauren
AU  - Bottoms, Lindsay M
PY  - 2026
DA  - 2026/09/30
TI  - Effects of Tart Cherry (<i>Prunus cerasus</i>) Supplementation on Overall Sleep Quality, Melatonin, and Inflammatory Biomarkers: A Systematic Review and Meta-Analysis
JO  - Recent Progress in Nutrition
SP  - 024
VL  - 06
IS  - 03
AB  - Poor sleep and insomnia are prevalent and carry substantial health and societal costs. Tart cherry (Prunus cerasus) contains polyphenols and melatonin and has been proposed as a dietary strategy to support sleep. This systematic review and meta-analysis synthesised evidence from randomised controlled trials (RCTs) evaluating the effects of tart cherry supplementation on sleep quality and biomarkers linked to inflammatory and melatonin-related pathways. PubMed, Scopus, and Web of Science were searched from inception to January 2026, alongside clinical trial registries. Eligible studies were human RCTs in adults (≥18 years) comparing tart cherry (juice, concentrate, powder, or capsules) with placebo or control. Sleep quality was the primary outcome with melatonin and inflammatory biomarkers extracted as secondary outcomes where available. Two reviewers screened records and assessed risk of bias using risk-of-bias tool for randomised trials (RoB 2.0) and certainty of evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE). Random-effects meta-analyses were conducted using Hedges’ g as the standardised mean difference. Ten RCTs involving 294 enrolled or randomised participants were included. The studies were published between 2010 and 2024. Interventions ranged from short protocols to 12 weeks and used juice-based products or capsules. Across all trials, tart cherry produced a small, non-significant improvement in overall sleep quality compared with placebo (Hedges’ g = 0.064; 95% CI -0.147 to 0.275; P = 0.552). In participants with insomnia (two trials), tart cherry significantly improved sleep quality (Hedges’ g = 0.732; 95% CI 0.051 to 1.412; P = 0.035). No significant effects were observed for melatonin or inflammatory biomarkers. Reported compliance was high (mean 95.76 ± 3.48%), and adverse events were infrequent. Overall risk-of-bias judgements ranged from some concerns to high. Certainty was very low for overall sleep quality in mixed populations and for inflammatory biomarkers, and low for the insomnia subgroup and melatonin. Tart cherry supplementation did not significantly improve pooled sleep quality across mixed adult populations. A benefit was observed in two small insomnia trials, but this finding was based on low-certainty evidence and should be considered preliminary. Larger, rigorously designed RCTs with standardised sleep outcomes and mechanistic biomarkers are required.
SN  - 2771-9871
UR  - https://doi.org/10.21926/rpn.2603024
DO  - 10.21926/rpn.2603024
ID  - Sinclair2026
ER  -