Big effect
Anthocyanins linked to a 0.3–0.5% drop in HbA1c — a modest but consistent effect across three studies.
This meta-analysis of three trials found a moderate, statistically reliable reduction in a key long-term blood sugar marker, though the effect size is modest and the picture is based on a limited number of studies.
A systematic review of three studies found that taking up to 320 mg of anthocyanins per day was tied to a small but consistent reduction in HbA1c (a measure of average blood sugar over the prior 2–3 months). The same review also noted improvements in inflammation and cholesterol, but the evidence for anthocyanins specifically on blood sugar control is moderate — encouraging, not definitive.
Where this fits in the evidence
Pillser has synthesized 3 studies on Anthocyanins for Reduced Hemoglobin A1c — overall evidence strength: Moderate.
Across all 3 studies in the database, anthocyanins consistently show beneficial effects on reducing hemoglobin A1c, with moderate effect sizes reported in the highest-quality evidence. A meta-analysis of 32 RCTs (1491 participants) found a statistically significant moderate reduction (SMD: -0.65; 95% CI: -1.00 to -0.29), and a systematic review reported modest reductions of ~0.3-0.5% HbA1c at doses up to 320 mg/day. The evidence predominantly comes from mixed populations (healthy and cardiometabolic disease).
The study
- Systematic Review
- 2026-05-26
- Molecules (Basel, Switzerland)
This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.