Effect of garlic intake on inflammatory mediators: a systematic review and meta-analysis of randomised controlled trials

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#garlic #humans #inflammation-mediators #randomized-controlled-trials-as-topic

Effect of garlic intake on inflammatory mediators: a systematic review and meta-analysis of randomised controlled trials

Koushki et al., 2021 | Postgrad Med J | Meta Analysis

Citation

Koushki Mehdi, Amiri-Dashatan Nasrin, ... Doustimotlagh Amir Hossein. Effect of garlic intake on inflammatory mediators: a systematic review and meta-analysis of randomised controlled trials. Postgrad Med J. 2021-Mar;97(1145):156-163. doi:10.1136/postgradmedj-2019-137267

Abstract

BACKGROUND: Garlic is a species in the onion genus, Allium. Data have shown that garlic has anti-inflammatory activity; however, the findings are inconclusive and inconsistent. We aimed to evaluate the impact of garlic intake on inflammatory mediators through systematic review and meta-analysis of existing data. METHODS: Electronic databases were completely investigated using databases of ISI Web of Science, Medline, Scopus, Cochrane Library and EMBASE until October 2019. A random effects model and the generic reverse variance procedure were used for quantitative data production. Sensitivity analyses and prespecified subgroup were done to evaluate potential heterogeneity. Random effect meta-regression was conducted to investigate the effects of possible confounders on the assessed effect size. RESULTS: Ten trials with one observational study, including 530 participants, met the eligibility criteria. The findings showed reduction in the tumour necrosis factor alpha (TNF-α) (-0.31 pg/mL, 95% CI -1.07 to 0.46) and C reactive protein (CRP) levels (-0.20 mg/L, 95% CI -1.4 to 1.05) following supplementation with garlic, although it had no marked impact on the interleukin 6 (IL-6) level (0.37 pg/mL, 95% CI -0.58 to 1.33). In the subgroup analysis, we found that garlic supplementation significantly decreased TNF-α, highly sensitive CRP and IL-6 levels in subgroups of >8, >6 and ≥4 weeks of intervention duration, respectively, and dose of garlic consumption between 2 and 2.4 g/day. CONCLUSION: These findings suggested that current evidence may support garlic as an adjunct to pharmacological management of metabolic diseases. PROSPERO REGISTRATION NUMBER: CRD42018108816.

Key Findings

Ten trials with one observational study, including 530 participants, met the eligibility criteria. The findings showed reduction in the tumour necrosis factor alpha (TNF-α) (-0.31 pg/mL, 95% CI -1.07 to 0.46) and C reactive protein (CRP) levels (-0.20 mg/L, 95% CI -1.4 to 1.05) following supplementation with garlic, although it had no marked impact on the interleukin 6 (IL-6) level (0.37 pg/mL, 95% CI -0.58 to 1.33). In the subgroup analysis, we found that garlic supplementation significantly de

Outcomes Measured

  • C-reactive protein
  • inflammatory markers

Population

Field Value
Population See abstract
Sample Size 530
Age Range See abstract
Condition See abstract

MeSH Terms

  • Garlic
  • Humans
  • Inflammation Mediators
  • Randomized Controlled Trials as Topic

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Systematic Review
  • Vertical: garlic

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09