Research

Hormonal

Consuming 1 cup (150g) of blueberries daily for 6 months improves endothelial function and reduces arterial stiffness in adults with metabolic syndrome, independent of changes in insulin resistance.

If you have metabolic syndrome, eating one cup of blueberries every day for six months can improve your blood vessel health and stiffness, which lowers cardiovascular risk. However, this amount of blueberries will not improve your insulin resistance or blood sugar control, so it should be part of a broader strategy that includes managing insulin sensitivity.

GoodQualifiesHIGH confidence
A daily intake of 1 cup of blueberries improved endothelial function (flow-mediated dilatation: +1.45%; 95% CI: 0.83%, 2.1%; P = 0.003), systemic arterial stiffness (augmentation index: –2.24%; 95% CI: –3.97%, –0.61%; P = 0.04)... Insulin resistance... were unaffected.
Peter J. Curtis et al. · American Journal of Clinical Nutrition · 2018

Why this rating

Double-blind, randomized controlled trial with a long duration (6 months) and clinically relevant endpoints, though the primary endpoint (insulin resistance) was negative.

Source

Blueberries improve biomarkers of cardiometabolic function in participants with metabolic syndrome—results from a 6-month, double-blind, randomized controlled trial

Peter J. Curtis et al. · American Journal of Clinical Nutrition · 2018

DOI 10.1093/ajcn/nqy380

rct · n=115Cited 242×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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