Endocrinology, Diabetes and Metabolism, cilt.9, sa.3, 2026 (ESCI, Scopus)
Background: Nanocurcumin has been developed to overcome the poor bioavailability of conventional curcumin and has been proposed as a potential adjunctive therapy for type 2 diabetes mellitus (T2DM). However, evidence regarding its clinical efficacy remains inconsistent. This systematic review and meta-analysis aimed to evaluate the effects of nanocurcumin supplementation on glycemic control, lipid profile, inflammatory markers and oxidative stress in patients with T2DM. Methods: A systematic search of PubMed, Scopus and the Cochrane Library was conducted from inception to October 2025 to identify randomized controlled trials (RCTs) assessing nanocurcumin supplementation in adults with T2DM. Eligible studies compared nanocurcumin with placebo or no intervention and reported outcomes related to glycemic indices, lipid parameters, inflammatory markers or oxidative stress. Pooled effect sizes were calculated using a random-effects model and expressed as standardized mean differences (SMDs) with 95% confidence intervals (CIs). Between-study heterogeneity was assessed using the I2 statistic. Results: Seven RCTs involving 453 participants were included. Nanocurcumin supplementation showed no significant effects on fasting blood glucose (SMD: −0.44; 95% CI: −2.16 to 1.28), HbA1c (SMD: 0.19; 95% CI: −1.26 to 1.65), or lipid profile parameters, including total cholesterol, LDL-C, HDL-C and triglycerides (all p > 0.05). No statistically significant reduction in C-reactive protein was observed (SMD: −0.78; 95% CI: −1.58 to 0.05). In contrast, nanocurcumin significantly increased total antioxidant capacity (SMD: 1.60; 95% CI: 0.93 to 2.31) and reduced malondialdehyde levels (SMD: −1.93; 95% CI: −3.19 to −0.66), indicating a robust antioxidative effect. Conclusions: Current evidence suggests that short-term nanocurcumin supplementation does not significantly improve glycemic control, lipid profile or systemic inflammation in patients with T2DM. However, preliminary evidence suggests that nanocurcumin may improve oxidative stress markers, reflected by improved total antioxidant capacity and reduced oxidative stress. These findings indicate that the potential clinical utility of nanocurcumin in T2DM may be primarily related to its antioxidative properties rather than direct metabolic modulation. Larger, long-term RCTs using standardized nanocurcumin formulations are warranted to determine its impact on diabetes-related complications and clinical outcomes. Although the primary pooled analysis showed no significant effects on lipid profile and CRP, sensitivity analysis revealed that exclusion of the study by Mansour et al. (2025), which had a longer duration and older participants, resulted in statistically significant reductions in total cholesterol and CRP. Given the substantial heterogeneity and limited number of studies, subgroup analyses were not feasible, and findings should be interpreted with caution.