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 4 studies on Anthocyanins for Reduced Hemoglobin A1c — overall evidence strength: Moderate.
Across 4 studies, all reported beneficial effects, with moderate effect sizes most common. In type 2 diabetes populations, median doses of 320 mg/day were associated with reductions in HbA1c of approximately 0.3–0.5%. Effects were typically observed at 56 days or longer.
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.