High blood pressure (hypertension) is the submarine of diseases,
silent but deadly. If the elevated blood pressure level is not
reduced, risks of heart disease, stroke, visual loss, and kidney
failure escalate. Early detection and treatment is lifesaving.
Part of effective treatment is often rational modification of
It has been a general, long-held belief that alcohol consumption,
in any form, in any quantity, raises blood pressure, and, therefore,
many of those at risk have been advised simply not to drink at
all. It is not so simple. Who drinks, and what they drink, and
how much, and in what pattern all appear to demand accounting.
Cardiovascular disease in young adults, especially women, has
not been as well studied as it has in older people, perhaps in
large part because it mostly only becomes apparent among middle-aged
and older men and older women. Some authorities have minimized
the beneficial cardiovascular effects of moderate drinking on
the young because the pay off does not become apparent until later
in life, shortsighted in the face of evidence of the many years
of insidious incubation required for these afflictions.
A recently published large, detailed project has helped illuminate
and stimulate by studying the effects of alcohol consumption on
the blood pressure of 70,891 women 25 to 42 years of age, part
of the seminal Nurses Health Study (Thadhani, et al.: Archives
of Internal Medicine, March 11, 2002).
The investigators found that "the association between alcohol
intake and risk of hypertension followed a J-shaped curve," that
is, modest drinkers were less bothered by blood pressure than
abstainers, and heavier drinkers had the highest blood pressuresa
most familiar relationship.
The specific results that follow are the relative risks (compared
to abstainers), adjusted for other major risk factors namely:
age, body mass index, race, smoking, cholesterol level, family
history of hypertension, physical activity and oral contraceptive
use. Women who averaged less than 0.25 drink per day have nearly
the same risk of hypertension as abstainers. Those who consumed
on average 0.26-0.50 drinks per day have a 14 percent lower risk;
0.51-1.00 drinks gives an 8 percent risk reduction as compared
with abstainers. The risks equalize at 1.01-1.50 drinks per day,
and climb to 20 and 30 percent higher at the ranges 1.51-2.00
and greater than 2.00 drinks per day, respectively. (One might
suppose that it would take appreciably more alcohol to bring about
similar effects in men, because men neutralize alcohol more effectively
than do women.)
The type of beverage seems to matter little, though there was
a suggestion that light drinking of beer may be particularly associated
with reduced risk of hypertension, but note the influence of antioxidants
commented on below.
The pattern of drinking does appear to matter. Episodic consumption
of more than 1.5 drinks per day does not increase the risk of
elevating blood pressure, whereas the risk does rise among women
with this level of consumption for at least five days per week.
This sort of effect has been noted by others, and is one of the
factors making the drinking/blood pressure relationship difficult
Stimulated by the Thadhani report, I surveyed and reviewed pertinent
medical literature applying to both sexes. Excessive alcohol has
been held responsible for ten percent of all cases of hypertension
by some epidemiologists. Physicians discovering elevated blood
pressure are obligated to inquire into drinking habits, and advise
Reduction of alcohol consumption to moderate levels often leads
to substantial reduction of the high blood pressure. The benefit
derived from moderation may add to other therapeutic efforts,
such as weight loss. Heavy drinking is associated with hypertension,
although the mechanism or mechanisms still need elucidation. They
are doubtlessly complex, and may act so differently under different
conditions that they may appear contradictory.
Randin, et al., and Victor and Hansen have investigated and pondered on, respectively, aspects of how alcohol might influence blood pressure (New England Journal of Finkel: BP 3 Medicine, June 29, 1995). Alcohol is thought to stimulate the release of cortiotropin-releasing hormone from the brain. This hormone (and alcohol)excites the sympathetic nervous system, thus increasing heart rate and cardiac output. These are short-term effects, so should not at this time be used as the basis for broad conclusions. Alcohol may sensitize blood vessels to other factors that raise blood pressure under certain
The blood pressure rise from alcohol administration is delayed,
occurring when blood levels of alcohol are decreasing. It was
speculated that it was breakdown products of alcohol, such as
acetaldehyde, that were working, or that time was required for
the hormonal effects to develop.
Hypertensives are regularly advised to abstain, but evidence is
strong that no harm comes to them, assuming reasonable control
of blood pressure, from moderate drinking. Certainly a glass of
wine daily for women and two for men have been repeatedly demonstrated
as not only harmless, but providing the same cardiovascular benefits
we all derive to a group that needs them even more than the rest
The polyphenolic antioxidants of wine help relax blood vessels
and hence lower blood pressure. The J-shaped curve rules.
In a rather severe test of wines effect upon blood pressure,
Foppa, et al., (Journal of Studies on Alcohol , March, 2002) had
obese hypertensive individuals drink red wine with their noon
meal, and found a fall in blood pressure that lasted all day.
Diebolt, et al., (Hypertension, August, 2001) fed red-wine polyphenols
to normotensive rats, and demonstrated a decrease in blood pressure
and more relaxed, healthier blood vessel walls. Fruit and vegetable
antioxidants have been reported associated with reduction in blood
pressure (John, et al.: Lancet, June 8, 2002). Red wine, even
when emasculated by removal of its alcohol, leads to relaxation
of blood vessel walls (Hashimoto, et al.: American Journal of
Cardiology, December 15, 2001).
What is our take-home message?
First, I would urge perusal of the list of major cardiovascular
risk factors in the fifth paragraph, to which add blood pressure
and excessive drinking, and attempt to correct those that require
and are susceptible to correction.
Second, obtain individualized advice from your individual physician.
Have your blood pressure checked: it may be dangerously high without
causing trouble...yet. If your blood pressure is elevated, you
may need medicine, which is highly likely to work well.
Third, with very rare exception, you need not fear enjoying wine
in moderation; it is likely to do you good.
Harvey E. Finkel, M.D. is clinical professor at Boston University
Medical Center and writes and lectures internationally on the
influences of alcohol upon health. He is member of the AIM Social
, Scientific and Medical Counsel.