New research suggests that drinking moderate amounts of alcohol could reduce the risk of heart failure.

Researchers at Harvard Medical School and Brigham and Women's Hospital found that people who drink up to seven drinks a week in early to middle age s associated with a 20 percent lower risk of men developing heart failure in the future when compared to people who did not drink at all, and a more modest 16 percent reduced risk for women.

Heart failure is a condition in which the heart can no longer pump blood around the body as well as it used to. The most common reason is that the heart muscle has been damaged, for instance by a heart attack. High blood pressure, heart muscle disease (cardiomyopathy), heart valve problems, an irregular heart beat (arrhythmia), viral infections, drinking excessive amounts of alcohol, consuming recreational drugs and the side-effects of radiotherapy treatment for cancer can all contribute to heart failure developing.

For the study, researchers collected and analyzed data from more than 14,600 people aged between 45-64 years who had been recruited to the Atherosclerosis Risk in Communities Study between 1987 and 1989 in four communities in the United States. They followed the participants for 24-25 years to the end of 2011, and they questioned them about their alcohol consumption at the start and at each of the three subsequent visits made at three-yearly intervals.

They defined a drink as one that contains 14g of alcohol, equivalent to approximately one small (125ml) glass of wine, just over half a pint or a third of a liter of beer, and less than one shot of liquor such as whisky or vodka. The study participants were divided into six categories: abstainers (people who recorded having drunk no alcohol at every visit by the researchers), former drinkers, people who drank up to seven drinks a week, or between 7-14 drinks, 14-21 drinks, or 21 or more drinks a week.

During the follow up period, 1,271 men and 1,237 women developed heart failure. Researchers found the lowest rate of heart failures occurred in those drinking up to seven drinks per week and the highest rate was seen among former drinkers.

"These findings suggest that drinking alcohol in moderation does not contribute to an increased risk of heart failure and may even be protective," researcher Scott Solomon said in a statement. "No level of alcohol intake was associated with a higher risk of heart failure. However, heavy alcohol use is certainly a risk factor for deaths from any cause."

They also found that the people who were classified as former drinkers at the start of the study had a higher risk of developing heart failure and of death from any cause when compared with abstainers.

"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," Solomon concluded.

The findings are detailed in the European Heart Journal.