Large meta-analysis finds regular cannabis use raises both pro-inflammatory and anti-inflammatory markers, not just one or the other

A meta-analysis of 46 studies found regular cannabinoid use associated with elevated levels of both pro- and anti-inflammatory biomarkers, suggesting immunomodulation rather than simple anti-inflammatory effects.

Murri, Martino Belvederi et al.·Brain·2026·Strong EvidenceMeta-Analysis
RTHC-08512Meta AnalysisStrong Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Meta-Analysis
Evidence
Strong Evidence
Sample
N=54,382

What This Study Found

Cannabis use was associated with higher anti-inflammatory biomarkers (SMD = 0.298, PD = 99%) and pro-inflammatory biomarkers (SMD = 0.166, PD = 100%). CBD RCTs suggested small pro-inflammatory marker increases (SMD = 0.15, PD = 90.9%). No consistent effects in prospective studies. Results varied by demographics, study design, and recency of use.

Key Numbers

46 studies, 54,382 participants, 190 effect sizes. Anti-inflammatory SMD = 0.298 (CrI 0.052-0.536). Pro-inflammatory SMD = 0.166 (CrI 0.122-0.209). CBD RCTs: pro-inflammatory SMD = 0.15. No major publication bias.

How They Did This

Systematic review and Bayesian multilevel meta-analysis of 46 studies (54,382 participants). 190 effect sizes pooled in three analyses. Bayesian hierarchical models accounted for clustering within studies and biomarkers.

Why This Research Matters

Cannabis is widely described as "anti-inflammatory," but this meta-analysis shows regular use modulates the immune system in both directions simultaneously, with implications for people using cannabis to manage inflammatory conditions.

The Bigger Picture

The "cannabis is anti-inflammatory" narrative oversimplifies a complex immunological picture. Cannabis acts as an immunomodulator, and the long-term consequences of dual modulation remain unknown.

What This Study Doesn't Tell Us

Most evidence from cross-sectional studies. Only 2 prospective and 10 RCTs. Heterogeneity in cannabinoid type, dose, and duration across studies.

Questions This Raises

  • ?Does dual pro/anti-inflammatory modulation benefit or harm people with autoimmune conditions?
  • ?What are the long-term cardiovascular consequences?

Trust & Context

Key Stat:
54,382 participants; both pro- and anti-inflammatory markers elevated with cannabis use
Evidence Grade:
Large meta-analysis with advanced Bayesian methods, but predominantly cross-sectional evidence limits causal interpretation.
Study Age:
2026 publication with search through October 2025
Original Title:
Regular cannabinoid use and inflammatory biomarkers: Systematic review and hierarchical meta-analysis.
Published In:
Brain, behavior, and immunity, 106517 (2026)
Database ID:
RTHC-08512

Evidence Hierarchy

Meta-Analysis / Systematic ReviewCombines many studies into one answer
This study
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Combines results from multiple studies to find an overall pattern.

What do these levels mean? →

Frequently Asked Questions

Is cannabis anti-inflammatory?

More accurately described as immunomodulatory. This meta-analysis found cannabis associated with increases in both anti-inflammatory and pro-inflammatory biomarkers.

Does CBD reduce inflammation?

RCT data in this meta-analysis suggested CBD may slightly increase pro-inflammatory markers. The assumption that CBD is purely anti-inflammatory may be an oversimplification.

Read More on RethinkTHC

Cite This Study

RTHC-08512·https://rethinkthc.com/research/RTHC-08512

APA

Murri, Martino Belvederi; Guglielmo, Riccardo; Zizzi, Alessio; Muscettola, Angela; Nanni, Maria Giulia; Dall'Oro, Manuela; Serafini, Gianluca; Inuggi, Alberto; Escelsior, Andrea; Amore, Mario; Grassi, Luigi. (2026). Regular cannabinoid use and inflammatory biomarkers: Systematic review and hierarchical meta-analysis.. Brain, behavior, and immunity, 106517. https://doi.org/10.1016/j.bbi.2026.106517

MLA

Murri, Martino Belvederi, et al. "Regular cannabinoid use and inflammatory biomarkers: Systematic review and hierarchical meta-analysis.." Brain, 2026. https://doi.org/10.1016/j.bbi.2026.106517

RethinkTHC

RethinkTHC Research Database. "Regular cannabinoid use and inflammatory biomarkers: Systema..." RTHC-08512. Retrieved from https://rethinkthc.com/research/murri-2026-regular-cannabinoid-use-and

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.