ORLANDO, Fla., Feb. 28 -- 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 today 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," Streppel said.
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.
FOR RELEASE: 4 p.m. EST, Wednesday Feb. 28, 2007
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.
Statements and conclusions of abstract authors that are presented at American Heart Association/American Stroke Association scientific meetings are solely those of the abstract authors and do not necessarily reflect association policy or position. The associations make no representation or warranty as to their accuracy or reliability.
Note: Presentation time is 6-8 p.m. EST, Feb. 28, 2007.