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Supplements · Metabolic & Cardiometabolic

green tea decreases blood pressure

In plain terms: Does green tea lower blood pressure?

Strong support Supplements 🔬 Includes disconfirming

Part of: 🧪 Green tea

RefutedContestedStrong support
consensus score 0.93

A little. Six meta-analyses agree it nudges blood pressure down — but only by about 1–3 points, which is real yet small. A nice habit, not a treatment for high blood pressure.

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

11 support 0 contradict 1 tested null 0 mixed · 12 sources, 11 independent groups

What the evidence shows

Six independent meta-analyses agree green tea lowers blood pressure, but the effect is SMALL and consistent — roughly 1–3 mmHg systolic — with several flagging low-to-moderate evidence quality and high heterogeneity. Real, but not a substitute for antihypertensive treatment.

The evidence (12)

SourceGradeStanceQualityFinding
Khalesi S et al.
2014 · Eur J Nutr
meta-analysis supports high Meta 13 RCTs: SBP -2.08 / DBP -1.71 mmHg vs control.
Peng X et al.
2014 · Sci Rep
meta-analysis supports high Meta 13 RCTs (n=1,367): SBP -1.98 / DBP -1.92 mmHg.
Li G et al.
2015 · J Hypertens
meta-analysis supports low Meta 14 RCTs (overweight/obese): SBP -1.42 / DBP -1.25 mmHg; overall evidence quality graded low.
Hartley L et al.
2013 · Cochrane Database Syst Rev
meta-analysis supports high Cochrane 7 green-tea RCTs: SBP -3.18/DBP -3.42 mmHg (not stable to sensitivity analysis).
Xu R et al.
2020 · Medicine (Baltimore)
meta-analysis supports moderate Meta 24 RCTs (n=1,697): SBP -1.17 / DBP -1.24 mmHg; significant heterogeneity.
Ghoflchi S et al.
2025 · Clin Ther
meta-analysis tested-null moderate In metabolic syndrome: no significant overall SBP/DBP change; benefit only in women subgroup.
Liu G et al.
2014 · Br J Nutr
meta-analysis supports moderate Meta 25 RCTs: green tea SBP -2.1/DBP -1.7 mmHg (long-term >=12 wk).
Mahdavi-Roshan M et al.
2020 · Complement Ther Med
meta-analysis supports moderate Meta 5 RCTs: SBP -4.81/DBP -1.98 mmHg in elevated-BP adults (green/black tea).
Yarmolinsky J et al.
2015 · Nutr Rev
meta-analysis supports moderate Meta 10 RCTs: SBP -2.36/DBP -1.77 mmHg in pre/hypertensives (green/black tea).
Onakpoya I et al.
2014 · Nutr Metab Cardiovasc Dis
meta-analysis supports high Meta 20 RCTs (n=1536): SBP -1.94 mmHg; no significant DBP.
Yildirim Ayaz E et al.
2023 · Altern Ther Health Med
meta-analysis supports moderate Meta 9 RCTs (healthy adults): SBP -2.99 / DBP -0.95 mmHg, zero heterogeneity.
Rezaei S et al.
2025 · Blood Press
meta-analysis supports moderate Dose-response meta 36 RCTs: SBP -1.08 / DBP -1.09 mmHg; high heterogeneity (I2=85%), no clear dose-response.

Disagree, or know a study we missed?

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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.