|
Binge Drinking May Be Bad for the Blood
Moderate alcohol use has
been shown to be healthier for the heart than abstinence or heavy
drinking, but consuming large amounts of alcohol in a short period
of time has been linked to higher death rates from all causes,
including cardiovascular ones.
Why such contradictory outcomes? Alcohol's effect on platelets
in the blood may provide part of the answer, a new Dutch study
suggests.
Platelets are the disk-shaped cells responsible for forming
clots and repairing small breaks in the walls of blood vessels.
When people binge on alcohol, it increases platelet aggregation,
meaning more platelets stick together, according to the study
in the October issue of Alcoholism: Clinical & Experimental
Research .
Drinking large qualities in a short span of time -- "binge drinking" --
also inhibits platelet adhesion, meaning platelets won't stick
as readily to a damaged vessel wall.
Preventing platelets from adhering to vessel walls could be
a good thing, said study author Dr. Dylan W. de Lange, a researcher
at the Thrombosis and Haemostasis Laboratory of the University
Medical Center in Utrecht. It may prevent blood vessels from
clogging and starving the heart or brain of needed oxygen.
It goes back to the delicately balanced process of blood clotting,
de Lange explained: "Too little of it and we bleed to death;
too much of it and we get cardiovascular infarction [heart attack]."
But at binge-consumption levels, it's doubtful any benefit from
diminished adhesion would completely compensate for the increase
in platelet aggregation, the authors said.
Strikingly, the researchers found that binge drinking red wine
did not increase platelet aggregation. That may help explain
why red wine drinkers exhibit less heart disease.
In the United States, scientists are trying to understand the
link between moderate drinking and lower cardiovascular risk.
The National Institute on Alcohol Abuse and Alcoholism defines
moderate drinking as no more than one drink per day for most
women, and no more than two drinks per day for most men.
The Dutch research is unusual because there have been few studies
on binge drinking's impact on the cardiovascular system, de Lange
said.
"And very, very few studies have focused on platelet adhesion," he
added. Of those studies, most focus on platelet aggregation "in
vitro," meaning in a test tube, not in humans.
For the experiment, 20 healthy volunteers drank either three
glasses of alcohol or red wine in a 45-minute period. Another
45 minutes were allowed for the alcohol to be absorbed. Blood
samples were collected 90 minutes after the start of the experiment.
The entire cycle was repeated, resulting in the volunteers consuming
six drinks in three hours.
In the lab, researchers looked at whether platelets from the
participants adhered to collagen or fibrinogen, two proteins
that are exposed when the normal internal lining of a vessel
is damaged. At the rate of blood flow normally found in vessels
that are narrowed by atherosclerosis, alcohol inhibited platelet
adhesion to fibrinogen, de Lange noted.
Should you drink moderately for your health? There still isn't
sufficient evidence to determine the optimal amount people might
want to consume for good health, de Lange cautioned.
"Alcohol still isn't a panacea for cardiovascular disease," he
said.
Visit the National
Institute on Alcohol Abuse and Alcoholism to learn more
about alcohol's effects on the heart.
(SOURCES: Dylan W. de Lange, M.D., researcher, Thrombosis and
Haemostasis Laboratory, University Medical Center, Utrecht, the
Netherlands; National Institute on Alcohol Abuse and Alcoholism,
Bethesda, Md.; October 2004 Alcoholism: Clinical & Experimental
Research ) Reference
Source 62
October
15, 2004
For
more information on how to prevent other diseases, use
PreventDisease.com's "Quick
Prevention Resources".
|