Effects of Ginkgo biloba extract on glycemic control, inflammatory markers, lipid profile, anthropometric indices, and safety parameters in patients with metabolic syndrome and type 2 diabetes: a meta-analysis

BACKGROUND: Ginkgo biloba extract (GBE) is widely used as adjunct therapy in metabolic syndrome (MetS) and type 2 diabetes (T2D), yet its effects on glycemic control, lipid profiles, inflammatory markers, and safety remain incompletely characterized. METHODS: This systematic review and meta-analysis of eight randomized controlled trials, including 1,507 subjects, evaluated the impact of GBE supplementation on glycemic profile, lipid parameters, inflammatory biomarkers, anthropometric indices, and safety outcomes. RESULTS: Compared with controls, GBE significantly reduced FBG (WMD - 13.88 mg/dL; 95% CI -24.61 to -3.15; p = 0.01) and improved insulin resistance (HOMA-IR; WMD - 3.64; 95% CI -5.71 to -1.56; p < 0.01) but did not significantly alter HbA1c or insulin levels. GBE also decreased anthropometric measures, including BMI (WMD - 0.85 kg/m²; 95% CI -1.53 to -0.18; p = 0.01), waist circumference (WMD - 2.67 cm; 95% CI -4.97 to -0.37; p = 0.02), and visceral adiposity index (WMD - 48.09; 95% CI -66.74 to -29.44; p = 0.01). Effects on lipid profiles were mixed, with no significant changes in total cholesterol, triglycerides, LDL, or HDL cholesterol. Inflammatory markers CRP (WMD - 1.16 mg/L), TNF-α (WMD - 58.3 pg/mL), and IL-6 (WMD - 14.53 pg/mL) were significantly reduced (all p < 0.05). The safety study showed minor but statistically significant elevations in ALT and AST. However, the therapeutic value of these findings is questionable due to short trial durations and lack of threshold-level data. There was no clinical hepatotoxicity episodes reported. Subgroup analysis suggested that higher doses (≥ 120 mg/day) and short intervention duration (≤ 90 days) yielded greater improvements. Furthermore, Evidence of publication bias was detected for FBG, TG, CRP, WC, TNF‑α, and BUN (Egger's test p < 0.05). CONCLUSIONS: GBE is associated with moderate but statistically significant improvements in short-term glycemic control, insulin sensitivity, inflammatory state, and obesity indices in MetS and T2D patients. Given the small effect sizes, substantial heterogeneity, lack of HbA1c improvement, and the possibility that publication bias will inflate estimates for numerous outcomes, these data should be viewed as preliminary and hypothesis-generating; they do not support the use of GBE as a standalone or first-line therapy. While lipid profile improvements were inconclusive, the extract appeared safe with manageable liver enzyme elevations. Although there were no side effects in these short-term trials, the minor elevations in liver enzymes should be interpreted with caution. Long-term hepatic safety has not been shown, thus periodic monitoring of liver function is recommended for extended use. These results are preliminary due to significant heterogeneity and a short trial period. Larger, patient-centered trials are needed to determine the therapeutic importance of these biochemical alterations.