Coffee consumption and blood pressure: a randomized, crossover clinical trial

J Gen Intern Med. May-Jun 1990;5(3):211-3. doi: 10.1007/BF02600536.

Abstract

Objective: To examine the effect of moderate coffee consumption on blood pressure over a prolonged period of time. Previous work in this area has used primarily purified caffeine.

Design: A prospective, randomized, crossover clinical trial.

Setting: A hypertension specialty outpatient clinic at the University of Tennessee, Memphis.

Patients: Healthy, young, white men who were moderate coffee drinkers (less than 6 cups/day) were recruited. Twenty-four subjects were randomized and 21 (average age 35.5 years) completed the trial.

Interventions: Subjects were randomized to one of two groups: Group A drank three or more cups of coffee/day for two months, then crossed over to abstaining from coffee for two months; group B abstained from coffee first, then crossed over to drinking coffee. Only filter-brewed coffee was used. Subjects were seen at monthly intervals for blood pressure measurements.

Measurements and main results: The average coffee consumption was 3.6 cups/day during the coffee-drinking phases. There was no difference between the coffee-drinking phase and the abstention phase in either systolic blood pressure (110.1 mmHg vs. 108.0 mmHg, respectively; 95% CI of difference -7.3, 2.5) or diastolic blood pressure (67.2 mmHg vs. 69.6 mmHg, respectively; 95% CI of difference -2.2, 6.4).

Conclusions: Moderate daily consumption of coffee does not elevate blood pressure.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Pressure / drug effects*
  • Coffee*
  • Humans
  • Male
  • Prospective Studies
  • Randomized Controlled Trials as Topic
  • Stimulation, Chemical
  • Time Factors

Substances

  • Coffee