REF-1653 · Mesas et al., 2011 · The American Journal of Clinical Nutrition, · Paper · PubMed

In people with hypertension, 200-300 mg of caffeine raised blood pressure by a mean 8.1/5.7 mmHg, a rise seen within the first hour and lasting at least 3 h, yet 2 weeks of regular coffee did not raise it and habitual coffee was not linked to cardiovascular disease

A meta-analysis of 5 acute trials, 3 two-week studies and 7 cohorts

Main caveat: Few studies per question (5 acute trials, 3 two-week studies), their sizes not in the abstract.
moderate evidenceMeasured on a mixed groupRead from the abstract only

Mesas and colleagues asked how caffeine and coffee affect blood pressure and cardiovascular disease in people with hypertension, where the effect was uncertain. They searched PubMed and EMBASE to 30 April 2011, taking data from controlled trials of caffeine or coffee on blood pressure and from cohort studies of habitual coffee and cardiovascular disease.

In 5 trials, 200-300 mg of caffeine raised systolic pressure by a mean 8.1 mmHg and diastolic by 5.7 mmHg; the rise appeared in the first hour and lasted at least 3 h. In 3 studies of 2 weeks, coffee did not raise blood pressure compared with a caffeine-free diet or with decaffeinated coffee.

Seven cohort studies found no link between habitual coffee and a higher risk of cardiovascular disease. The authors conclude that caffeine raises blood pressure acutely for at least 3 h in hypertensive people, but that the evidence does not support a link between longer-term coffee and raised blood pressure, or between habitual coffee and cardiovascular risk, in this group.

Participants

People with hypertension in all included studies; both sexes and ages from adult to over 80 by the PubMed indexing.
Numbers of participants, their treatment and their habitual caffeine intake: not in the abstract.

Methods

Search: PubMed and EMBASE, to 30 April 2011.
Included: controlled trials of caffeine or coffee and blood-pressure change (acute and longer term); cohort studies of habitual coffee and cardiovascular disease.
Studies: 5 acute trials (200-300 mg caffeine), 3 longer-term studies (2 weeks of coffee against a caffeine-free diet or decaffeinated coffee), 7 cohort studies.
Quality or risk-of-bias assessment: not in the abstract.

Key Results

QuestionStudiesResult
Acute: 200-300 mg caffeine5 trialssystolic +8.1 mmHg (95% CI 5.7 to 10.6); diastolic +5.7 mmHg (4.1 to 7.4)
Time course of the acute rise5 trialsseen within the first hour; lasted ≥3 h
2 weeks of coffee vs caffeine-free diet or decaf3 studiesno increase in blood pressure
Habitual coffee and cardiovascular disease7 cohortsno association with higher risk

Practical Application

In people with hypertension, a blood-pressure reading taken in the 3 h or more after caffeine can read high. In the pooled trials, 200-300 mg raised pressure by a mean 8.1/5.7 mmHg; the rise appeared within the first hour and lasted at least 3 h.
The acute rise did not carry over into regular drinking. Two weeks of coffee did not raise blood pressure against caffeine-free or decaffeinated controls, and habitual coffee was not linked to cardiovascular disease in 7 cohorts.
Inference, not tested here: to compare readings over time, take them at the same point relative to coffee, ideally before the first cup.
Refer-out: for an athlete with high or treated blood pressure, the doctor decides on caffeine and on what the readings mean; the assistant does not diagnose or change medication.
Not settled by this design / not from this paper: athletes with normal blood pressure; blood pressure during exercise after caffeine; doses above 300 mg; whether habitual drinkers showed the same acute rise (not in the abstract).

Limitations

Few studies per question (5 acute trials, 3 two-week studies), their sizes not in the abstract.
No risk-of-bias or quality assessment reported in the abstract; the cohort evidence is observational.
Hypertensive people only; the habitual caffeine intake of the acute-trial participants is not in the abstract.
The two-week studies are short; longer use was covered only by the cohorts, and only for cardiovascular disease, not blood pressure.
Written from the abstract and the PubMed record; full text not read.
How this entry was checked and changed
Why this level

risk of bias not read (abstract only; no risk-of-bias or quality assessment is reported in the abstract); the acute estimate rests on 5 trials whose sizes are not in the abstract; blood pressure is the subject of this entry, not a stand-in for an outcome, so no marker step

Content correction 2026-11-07
2026-11-07: added from the abstract and the PubMed record; level B+ (meta-analysis of trials and cohorts, risk of bias not read; abstract only).