A new study conducted by Harvard scientists concluded that moderate consumption of alcohol (moderate!) can lead to lower risk of heart failure. The study, which was conducted on over 14,000 men and women aged 45-64 found that a small drink every day is associated with a 20 percent lower risk of men developing heart failure and 16 percent reduced risk for women.
Alcohol is generally regarded as unhealthy. However, alcohol has its benefits; in the Mediterranean diet, moderate consumption of red wine is indicated, and the Mediterranean diet is one of the best for the heart. Previous studies have also found that moderate alcohol consumption is associated with better memory later in life. This study found that alcohol itself can be good for the heart.
"The findings suggest that drinking alcohol in moderation does not contribute to an increased risk of heart failure and may even be protective," said Scott Solomon, professor of medicine at Harvard Medical School and senior physician at Brigham and Women's Hospital in Boston.
A cocktail a day keeps the doctor away
The team defines "a drink" as one small (125ml) glass of wine, just over half a pint or a third of a litre of beer and less than one shot of liquor such as whisky or vodka. The participants in the study were divided into six categories:
- former drinkers, current abstainers
- people who drink 1-7 drinks a week
- people who drink 7-14 drinks a week
- people who drink 14-21 drinks a week
- people who drink over 21 drinks a week
During the study, almost 20 percent (1,271 men and 1,237 women) of participants developed heart failure. Out of those, the lowest rate of heart failures occurred in those drinking up to seven drinks per week and interestingly enough, the highest occurrence was in former drinkers. Men who drank between 1 and 7 drinks a week had a 20% reduced risk of developing heart failure compared to abstainers, while in the women, that risk was reduced by 14%.
It's quite possibly that the reason why former drinkers showed the highest rates of heart failure is that they had a medical reason to quite drinking in the first place. The sex difference seems statistically relevant, but it's not yet clear why this happens.
"There are a number of different mechanisms by which the effects of alcohol on the heart may differ by sex," write the researchers in their study. "Women have a higher proportion of body fat and absorb and metabolize alcohol differently than men, attaining higher blood alcohol concentrations for a given amount of alcohol consumed."
The study was not raw, and scientists controlled, as much as possible, for other elements which may impact the results. They compensated for age, diabetes, high blood pressure, heart disease or heart attacks, body mass index, cholesterol levels, physical activity, education and smoking,
"We did adjust our results to take account, as far as possible, for a variety of other lifestyle factors that could affect a person's risk," Solomon explained.
However, as we pointed out several times, correlation does not imply causation. The fact that moderate drinkers show a lower chance of heart failure does not necessarily mean that it's the alcohol doing the good.
"It is important to bear in mind that our study shows there is an association between drinking moderate amounts of alcohol and a lower risk of heart failure but this does not necessarily mean that moderate alcohol consumption causes the lowered risk, although we did adjust our results to take account, as far as possible, for a variety of other lifestyle factors that could affect a person's risk."
- A. Goncalves, B. Claggett, P. S. Jhund, W. Rosamond, A. Deswal, D. Aguilar, A. M. Shah, S. Cheng, S. D. Solomon. Alcohol consumption and risk of heart failure: the Atherosclerosis Risk in Communities Study. European Heart Journal, 2015; DOI: 10.1093/eurheartj/ehu514