Supplements · Metabolic & Cardiometabolic

green tea decreases blood pressure

In plain terms: Does green tea lower blood pressure?

Strong support Supplements 🔬 Includes disconfirming

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.

📅 Last reviewed: 2026-07-15 ⓘ

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

12 support 0 contradict 1 tested null 1 mixed · 14 sources, 12 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.

Cochrane agrees with us see how our grade compares ▾

Cochrane review 2013 · Not GRADE-rated Agrees with our grade

authors advise caution due to small number of trials. Green tea SBP MD -3.18 mmHg (95% CI -5.25 to -1.11) and DBP MD -3.42 mmHg (95% CI -4.54 to -2.30), statistically significant but not stable to sensitivity analysis.

“There are very few long-term studies to date examining green or black tea for the primary prevention of CVD. The limited evidence suggests that tea has favourable effects on CVD risk factors, but due to the small number of trials contributing to each analysis the results should be treated with some caution and further high quality trials with longer-term follow-up are needed to confirm this.”

Why we agree: we reached the same direction independently, from our own appraisal of 14 sources. Two methods landing in the same place is a stronger signal than either alone.

What is Cochrane, and why trust it?

Cochrane produces systematic reviews: instead of running a new study, they gather every trial ever done on a question, judge how well each was run, and pool the results. They take no commercial or industry funding, which is why the medical community treats their reviews as a gold standard — and why we check our own verdicts against theirs.

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The evidence (14)

Source	Grade	Stance	Quality	Finding
Taati B et al 2026 · study_type: observational	observational	mixed	low	Narrative evidence-based review of 31 clinical studies on plant-based supplements + exercise for BP; states green tea shows variable BP outcomes depending on caffeine content, exercise modality, and participant health status, unlike beetroo
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.
Hoseini E et al 2025 · study_type: animal	animal	supports	moderate	Rat study: olanzapine significantly raised systolic BP (SBP) among other metabolic derangements; co-administration of green tea catechins EGCG or ECG (10-40 mg/kg) significantly suppressed the olanzapine-induced SBP elevation.
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.

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