Is the protective effect of alcohol a myth?

Higher social status, better overall health could explain the link, researchers say

A major French study links moderate drinking to a lower risk for cardiovascular disease, but challenges the notion that moderate drinking is the cause of the benefit. Instead, the researchers say, people who drink moderately tend to have a higher social status, exercise more, suffer less depression and enjoy superior health overall compared to both heavy drinkers and lifetime abstainers.

Boris Hansel and colleagues studied 149,773 people from the Urban Paris-Ile-de-France Cohort and split them into four groups; never, low, moderate and high alcohol intake. The low and moderate groups of both males and females displayed a more favourable health status than the groups that never drunk or drunk large amounts. Moderate male drinkers were more likely to have lower cardiovascular risk, heart rate, stress, depression and body mass index. They also scored higher with subjective health measures such as respiratory function and physical activity. Similar trends were seen in moderate female drinkers who had lower blood pressure and waist circumference. Importantly, the findings showed moderate alcohol consumption is a powerful general indicator of optimal social status and this could be a key reason for improved health in these subjects. For both genders, alcohol intake was strongly associated with increased concentrations of High Density Lipoprotein (HDL) in the blood plasma. However, it could not be shown that the influence of alcohol on HDL had a cardio-protective effect and the authors stress that these results are not necessarily evidence of alcohol providing cardiovascular protection.

Commenting on the study, Dr Carla A. Green, a senior investigator at the Kaiser Permanente Center for Health Research in Portland, Ore., said, “There is increasing evidence that a lot of the health benefits that have been attributed to alcohol consumption are due to healthy habits that also include moderate alcohol consumption.”

There might be some beneficial effect of alcohol itself, but “based on research to date, it has a much smaller effect than has been thought in the past,” Green said.

She cited a recent study she led on alcohol consumption, health status and use of health services. “Heavy drinkers appear to avoid going to doctors,” Green said. “The reasons include shame and not wanting to be lectured. So heavy drinkers are not going to get the health care they need and will get sicker.”

SOURCES: Boris Hansel, M.D., endocrinologist, Hopital de la Pitie, Paris; Arthur Klatsky, M.D., senior consultant, cardiology, Kaiser Pemanente Health Plan, Oakland, Calif.; Carla A. Green, Ph.D., senior investigator, Kaiser Permanente Center for Health research, Portland, Ore.; May 2010 European Journal of Clinical Nutrition