Drinking a little alcohol every
day, especially wine, may be associated with an increase
in life expectancy. That's the conclusion of Dutch researchers
who reported the findings of their study yesterday at
the American Heart Association's 47th Annual Conference
on Cardiovascular Disease Epidemiology and Prevention.
The researchers found that a light intake
of alcohol (on average less than one glass per day) was
associated with a lower rate of cardiovascular death and
death from all causes. When compared to spirits and beer,
consumption of small amounts of wine, about a half a glass
a day, was associated with the lowest levels of all-cause
and cardiovascular deaths.
"Our study showed that long-term,
light alcohol intake among middle-aged men was associated
not only with lower cardiovascular and all-cause death risk,
but also with longer life expectancy at age 50," said
Martinette T. Streppel, lead author of the study and a Ph.D.
student in the Division of Human Nutrition at Wageningen
University and National Institute for Public Health and
the Environment (RIVM) in Bilthoven, The Netherlands. "Furthermore,
long-term light wine consumption is associated with a further
protective effect when compared to that of light-to-moderate
alcohol intake of other types."
Previous studies have shown that light
to moderate alcohol intake is associated with a lower risk
of cardiovascular death. However, it remained unclear whether
a specific beverage was associated with more benefit and
whether the use of long-term alcohol consumption was associated
with increased life expectancy. Studies such as this cannot
definitively show whether the agent being studied has a
causal effect on health.
The Netherlands study — called the Zutphen
Study — involved a cohort of 1,373 men born between 1900
and 1920 who were surveyed in detail about alcohol consumption
seven times over 40 years. The participants, all from Zutphen,
an industrial town in the eastern part of the Netherlands
, were followed until death or until the final survey taken
among survivors in mid-2000. The surveys included drinking
habits, dietary habits, body mass index, smoking habits
and the prevalence of heart attack, stroke, diabetes and
cancer. The statistics on alcohol consumption were adjusted
to account for other risk factors.
The researchers found that long-term, light
alcohol intake of less than or equal to 20 grams per day
(1 glass of alcoholic beverage contains 10 grams of alcohol,
1 ounce = ~30 mL of alcoholic beverage) compared to no alcohol
intake was associated with a 36 percent lower relative risk
of all-cause death and a 34 lower relative risk of cardiovascular
death. The average long-term daily intake of the men throughout
the 40-year study was six grams based on any alcohol intake
of more than zero and up to 20 grams. The long-term average
intake of six grams of alcohol is equal to one four-ounce
beer, one two-ounce glass of wine or one one-ounce glass
of spirits, daily.
When the researchers looked independently
at wine consumption, the associated risk reduction was greater.
Participants who drank on average half a glass, or 1.5 ounces,
of wine per day, over a long period, had a 40 percent lower
rate of all-cause death and a 48 percent lower incidence
of cardiovascular death, compared to the non-wine drinkers.
Researchers said life expectancy was 3.8
years higher in those men who drank wine compared to those
who did not drink alcoholic beverages. Life expectancy of
wine users was more than two years longer than users of
other alcoholic beverages. Men with a long-term alcohol
intake less than or equal to 20 grams per day had a 1.6-year-higher
life expectancy, compared to those who consumed no alcohol.
Most of the previous studies assessed alcohol
intake at baseline; however, in this study researchers collected
detailed information seven times over 40 years. "Consumption
patterns usually change during life," Streppel said.
"This enabled us to study the effects of long-term
alcohol intake on mortality." Researchers found that
the number of alcohol users nearly doubled from 45 percent
in 1960 to 85 percent in the 2000 survey. Average alcohol
consumption rose and then fell at various points during
the study. Users' consumption was eight grams a day in 1960,
then survivors' consumption was 18 grams a day in 1985,
dropping to 13 grams per day in 2000. The percentage of
wine users increased during follow-up from 2 percent in
1960 to more than 40 percent among the survivors in 2000.
"One can speculate that a protective effect of light
alcohol intake could be due to an increase in high-density
lipoprotein (HDL) cholesterol, or to a reduction in blood
clotting, due to an inhibition of platelet aggregation,"
Furthermore, red wine consumption may have
an additional health benefit because the polyphenolic compounds
contained in wine have been seen in animal to interfere
with the formation, progression and rupture of atherosclerotic
plaques — the build-up of fatty tissue in the arteries that
can result in stroke or heart attack.
"Those people who already consume
alcoholic beverages should do so lightly (1 to 2 glasses
per day) and preferably drink wine," Streppel said.
"The cardio-protective effects of alcohol and wine
only held up for light alcohol consumption in middle-aged
men. Heavy alcohol consumption may cause accidents and diseases
such as cancer and cirrhosis of the liver, even though this
was not observed in our study. Since alcohol consumption
can be addictive, starting to drink alcohol because of its
positive health benefits is not advised."
How alcohol or wine might affect cardiovascular
risk merits further research, but right now the American
Heart Association does not recommend beginning to drink
wine or any other form of alcohol to gain these potential
benefits. The association does recommend that to reduce
your risk you should talk to your doctor about lowering
your cholesterol and blood pressure, controlling your weight,
getting enough physical activity and following a healthy
diet and quit smoking, if you smoke. There is no scientific
proof that drinking wine or any other alcoholic beverage
can replace these conventional measures.
The study was partly funded by a grant
from the former Inspectorate for Health and Protection and
Veterinary Public Health, which is presently integrated
in the Food and Consumer Product Safety Authority, The Netherlands
and partly by the National Institute for Public Health and
the Environment (RIVM), The Netherlands. Co authors are
Marga C. Ocke, Ph.D.; Hendriek C. Boshuizen, Ph.D.; Frans
J. Kok, Ph.D. and Daan Kromhout, Ph.D.
Delhi , March 1, 2007