Drinking four or five cups of coffee a day raises blood
pressure and stress-related hormones throughout the day,
researchers report in two studies.

In one study, researchers at Duke University Medical Center
in Durham studied 72 habitual coffee drinkers. They found
these people had a 32 percent increase in the stress
hormone adrenaline and a 14 percent increase in
noradrenalin compared with days they abstained from
coffee.

Adrenaline and noradrenalin help the body respond to
stress, but overproduction can damage the heart over an
extended period of time. Coffee also increased their blood
pressure by an average of three points, researchers
reported today at the 1999 Society of Behavioral Medicine
meeting in San Diego.

Another recent study published in the March issue of
Hypertension found chronic coffee consumption increased
systolic blood pressure by an average of 2.4 millimeters
per mercury (mm Hg) and an average of 1.2 mm Hg for
diastolic blood pressure.

Researchers at Johns Hopkins University in Baltimore also
calculated each cup of coffee consumed during the day
raised systolic blood pressure by 0.8 mm Hg and diastolic
blood pressure by 0.4 mm Hg.

Investigators also pointed out that the effects of coffee
on blood pressure was more pronounced among young people.