Curcumin/Turmeric Supplementation on Glycemic Control in Adults With Prediabetes and Type 2 Diabetes: A Systematic Review and Dose-Response Meta-Analysis.
- 2026-04
- Food science & nutrition 14(4)
- PubMed: 42005325
- DOI: 10.1002/fsn3.71748
Study Design
- Type
- Review
- Population
- individuals with prediabetes or type 2 diabetes
- Methods
- Systematic review and meta-analysis of RCTs; random-effects models
Curcumin and turmeric have demonstrated potential hypoglycemic properties in preclinical studies, but findings from human randomized controlled trials (RCTs) in prediabetes and type 2 diabetes (T2D) are inconsistent. PubMed, Scopus, and Web of Science ISI databases were comprehensively searched until August 2025 (25/08/2025) to find eligible RCTs. Overall effect sizes were estimated based on the random-effect models and presented as weighted mean differences (WMD) with 95% confidence intervals (95% CI). All analyses were performed using version 17.0 (Stata Corp., College Station, TX, USA). Thirty-four eligible RCTs (39 treatment arms) were included in this review. Curcumin/turmeric supplementation significantly reduced fasting blood glucose (FBG) (WMD = -10.15 mg/dL; 95% CI: -12.59, -7.72), hemoglobin A1c (HbA1c) (WMD = -0.32%; 95% CI: -0.43, -0.21), fasting insulin (WMD = -0.69 μU/ml; 95% CI: -1.27, -0.12), homeostatic model assessment of insulin resistance (HOMA-IR) (WMD = -0.46; 95% CI: -0.60, -0.32), and oral glucose tolerance test (OGTT) (WMD = -11.53 mg/dL; 95% CI: -22.68, -0.44) compared to control groups. However, no significant alteration in homeostatic model assessment of β-cell function (HOMA-B) levels was detected, followed by Curcumin or turmeric supplementation in comparison to the control groups. Subgroup analyses indicated that efficacy was modified by health status (T2D vs. prediabetes), dosage (≥ 1 g/day more effective), and formulation. This meta-analysis revealed that curcumin/turmeric supplementation may improve glycemic control in individuals with prediabetes or T2D. Despite positive findings, significant heterogeneity across studies necessitates caution. Furthermore, future high-quality RCTs are required to reach a firm conclusion.
Research Insights
| Supplement | Dose | Health Outcome | Effect Type | Effect Size | Source |
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