Do anthocyanins from berries help your heart and blood sugar?

Higher anthocyanin intake is linked to lower diabetes risk in big studies. Trials show better artery flow; blood sugar and blood pressure results are mixed.

Published October 2026

Short answer

Early evidence: more anthocyanins is linked to lower diabetes risk, and trials show better artery flow, but blood sugar and blood pressure do not clearly change. Evidence grade C (Limited). Mostly observational cohort meta-analyses for disease outcomes, conflicting trial reviews on blood sugar and blood pressure, and a surrogate-only artery benefit; downgraded for inconsistency and observational design.

Key takeaways

Higher anthocyanin intake is linked to 11 to 15% lower type 2 diabetes risk in cohort meta-analyses [1][2].
Heart attack and cardiovascular death links appear in some cohort analyses, but another review found no link to heart attacks [1][3].
In 65 trials, anthocyanins improved artery flow by about 1.4% [1].
Trials have not shown a clear change in blood sugar, cholesterol or blood pressure in healthy people [1].
Cohort results show association, not cause, so they cannot prove that berries prevent heart disease or diabetes [1].

The short version

Anthocyanins are a group of plant pigments found mainly in berries [4]. Higher intake is linked to lower type 2 diabetes risk and, in some analyses, lower heart attack and cardiovascular death risk [2][1]. Trials show better artery flow, but they do not show a clear drop in blood sugar or blood pressure in healthy people [1].

What the studies show

The largest recent review pooled 18 cohort studies. Comparing the highest with the lowest intake, heart attack risk was about 18% lower, type 2 diabetes risk about 11% lower and cardiovascular death about 9% lower; stroke risk did not change [1].

A 2016 meta-analysis of three cohorts, with about 200,000 people, found 15% lower type 2 diabetes risk with higher anthocyanin intake [2]. A 2019 meta-analysis found 9% lower coronary heart disease risk, but no link to heart attacks, stroke or total cardiovascular disease [3].

In 65 randomised trials, chronic anthocyanin intake improved flow-mediated dilation, a test of how well arteries widen, by about 1.4% [1]. Insulin fell slightly, while lipids, blood pressure, glucose and HOMA-IR did not change in healthy participants [1].

Earlier, a 2017 meta-analysis of 32 trials with 1,491 people, both healthy and with cardiometabolic disease, found lower fasting glucose and HbA1c, a three-month blood sugar measure, as well as lower LDL cholesterol [5].

In a 45-person trial in people with metabolic syndrome, adding 26 g of freeze-dried blueberries to a high-fat, high-sugar drink raised blood glucose at one hour (8.2 vs 6.9 mmol/L) but lowered it at three hours (4.3 vs 5.1 mmol/L) [6].

The nuances

Observational studies show association, not cause [1]. The heart findings are also less consistent: the 2019 review found no link to heart attacks [3].

Blood pressure is not clearly improved. A 2026 meta-analysis of nine trials in adults with high or raised blood pressure found berry supplements lowered systolic pressure by 2.35 mmHg, a change that was not statistically significant, and its certainty was low to very low [7]. One 12-week trial of 61 healthy older adults found a 3.59 mmHg fall in 24-hour systolic pressure with 26 g of freeze-dried wild blueberry powder, about 302 mg of anthocyanins a day [8].

A 2023 meta-analysis of anthocyanin-rich foods in people with metabolic syndrome found LDL about 8 mg/dL lower, but the certainty was very low [9].

Safety: the two blueberry trials we read, with 61 and 45 people, do not mention side effects in their abstracts [8][6]. We found no studies on pregnancy, breastfeeding, kidney disease or interactions with medicines. Concentrated supplements are not the same as eating berries, so if you take blood thinners, diabetes medicines or blood pressure medicines, ask a doctor first. See the anthocyanins page for more.

What this means for you

Berries are a food, and the trials test food and supplement amounts. The honest read is a small effect on artery flow in trials [1], and lower diabetes risk in people who eat more of these foods over time [2]. Trials have not shown a clear drop in blood sugar or blood pressure in healthy people [1]. Eating berries as part of a varied diet fits this evidence. For heart or blood sugar goals, talk to your doctor, especially if you take medicines. See also the blueberries page.

Go deeper

Anthocyanins — Anthocyanins are plant pigments found mainly in berries.
Blueberries — Blueberries may help memory in older adults with mild memory decline: a meta-analysis of nine trials found better episodic memory (memory for everyday events)…