May 8, 2009 — Drinking up to half a glass of wine daily may increase longevity by 5 years in men, but more studies are needed, according to the results of a study reported online first in the April 30 issue of the Journal of Epidemiology and Community Health.
“Light to moderate alcohol intake lowers the risk of cardiovascular mortality, but whether this protective effect can be attributed to a specific type of beverage remains unclear,” write M.T. Streppel, from the National Institute for Public Health and the Environment, Bilthoven, the Netherlands, and colleagues. “Moreover, little is known about the effects of long-term alcohol intake on life expectancy.”
The goal of this analysis was to determine the effect of long-term alcohol intake and types of alcoholic beverages consumed on cardiovascular mortality and life expectancy at age 50 years. The study cohort consisted of 1373 men enrolled in the Zutphen Study who were born between 1900 and 1920 and evaluated repeatedly between 1960 and 2000.
Time-dependent Cox regression models were used to calculate hazard ratios (HRs) for total alcohol intake and for intake of alcohol from wine, beer, and spirits. Areas under survival curves were used to assess life expectancy at age 50 years. Light alcohol intake was defined as consumption of not more than 20 g/day.
Compared with no alcohol consumption, long-term light alcohol intake was strongly and inversely associated with risks for cerebrovascular mortality (HR, 0.43; 95% confidence interval [CI], 0.26 – 0.70), total cardiovascular mortality (HR, 0.70; 95% CI, 0.55 – 0.89), and all-cause mortality (HR, 0.75; 95% CI, 0.63 – 0.91).
Long-term wine consumption averaging less than half a glass per day was strongly and inversely associated with coronary heart disease (HR, 0.61; 95% CI, 0.41 – 0.89), total cardiovascular mortality (HR, 0.68; 95% CI, 0.53 – 0.86), and all-cause mortality (HR, 0.73; 95% CI, 0.62 – 0.87), independent of total alcohol intake. Differences in socioeconomic status did not explain these results. Compared with men who did not consume alcohol, men who drank, on average, less than half a glass of wine per day had a life expectancy about 5 years longer.
“Long-term light alcohol intake lowered cardiovascular and all-cause mortality risk and increased life expectancy,” the study authors write. “Light wine consumption was associated with 5 years longer life expectancy; however, more studies are needed to verify this result.”
Limitations of this study include lack of data on drinking frequency, average long-term alcohol intake was relatively low, most participants used more than 1 type of alcoholic beverage in their usual diet, and for those men who were newly included in the study in 1985, information on alcohol intake was missing for the period 1960 to 1970.
“The inverse associations between wine consumption and mortality remained after adjustment for total alcohol intake,” the study authors conclude. “Wine consumers had a 5 years longer life expectancy compared with no alcohol consumers; however, more studies are needed to draw conclusions on the strength of the association between wine consumption and mortality.”
The former Inspectorate for Health Protection and Veterinary Public Health, at present integrated in the Food and Consumer Product Safety Authority, the Netherlands, supported this study. The authors have disclosed no relevant financial relationships.
J Epidemiol Community Health. Published online April 30, 2009.
An observed U- or J-shaped association between alcohol intake and all-cause mortality may be attributed to a lower risk for cardiovascular disease mortality in light to moderate drinkers. The mechanism underlying the protective effect of light to moderate alcohol intake may be an increase in high-density lipoprotein cholesterol and prevention of blood clotting and reduction in platelet aggregation.
The polyphenols in red wine may offer an additional health benefit because these compounds inhibit the formation, progression, and rupture of atherosclerotic plaques and improve endothelial function. However, some studies suggest that the apparent benefits of wine consumption vs other alcoholic beverages may reflect differences in socioeconomic status and dietary and other lifestyle habits.