Skip to main content
Evidence-Based Supplement Research
Evidence-Based Supplement Research
Pillser
Search
Sign UpLog In

Gardenia and Reduced Fasting Blood Glucose Levels

Research synthesisLow evidenceMixed effect size3 studies · 2 beneficial · 1 neutral · 0 harmful

Across 3 studies, 2 reported beneficial effects (1 moderate, 1 small) and 1 showed a neutral effect, suggesting a predominantly beneficial but mixed effect size for Gardenia (crocin) on reduced fasting blood glucose. The only study reporting a dose used 15 mg daily (two tablets), and the median duration among the single study reporting it was 56 days, indicating effects may be observed at approximately 8 weeks. All studies were in clinical populations (e.g., metabolic syndrome, type 2 diabetes), with meta-analytic evidence showing a moderate effect (FBG reduction of -14.10 mg/dL).

  • Effective dose range: 15 mg daily (two tablets per day)
  • Studied populations: patients with metabolic syndrome, patients with type-2 diabetes mellitus

Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. Two of the three studies are meta-analyses/reviews that include overlapping trials, which may inflate consistency. The only RCT (evidence score 6) showed a neutral effect, contrasting with the meta-analytic findings, indicating possible heterogeneity or publication bias.

Generated Jun 9, 2026
Doses used in studies
  • mg/day: 15 (median 15, IQR 15–15) — 1 study
Time to effect
Median: 8 weeks · IQR 8 weeks–8 weeks · Range 8 weeks–8 weeks — Reported in 1 of 3 studies
Safety in these studies
3 of 3 papers
Back to top