Drinking three to five alcohol beverages weekly may benefit heart health.
According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), almost 87% of adults in the US have consumed alcohol at some point in their lifetime, and more than 56% have had a drink in the past month.
While there is no doubt that excessive alcohol use is detrimental to health, studies are increasingly suggesting that moderate drinking may have its benefits.
In December 2015, for example, Medical News Today reported on a study suggesting moderate alcohol intake may lower death rates from early-stage Alzheimer's, while another study suggested that consuming up to seven drinks weekly may lower heart failure risk.
The two new studies further support the link between moderate alcohol intake and better heart health, after finding that drinking three to five alcohol beverages a week may reduce the risk of heart attack and heart failure.
33% lower heart failure risk with moderate drinking
Both studies were conducted by the same team, including Imre Janszky, a professor of social medicine at the Norwegian University of Science and Technology (NTNU).
For the first study, published in the International Journal of Cardiology, the team analyzed the data of 60,665 individuals free of heart failure who were enrolled in the longitudinal HUNT 2 Nord-Trøndelag Health Study between 1995-1997.
The researchers assessed the self-reported drinking habits of the participants and assessed the incidence of heart failure up until 2008. During follow-up, 1,588 of the participants developed heart failure.
The team found that compared with participants who never or rarely consumed alcohol, those who consumed around three to five drinks a week had a 33% lower risk of heart failure.
Additionally, the researchers found that heart failure risk was reduced with more frequent drinking; subjects who drank alcohol five times or more a month had a 21% lower risk of heart failure, compared with non-drinkers and those who rarely drank, while participants who drank one to five times monthly had a 2% lower risk of heart failure.
But there is no need to drink daily to have a healthy heart
In the second study, published in the Journal of Internal Medicine, Janszky assessed the data of 58,827 participants who were also part of the HUNT study and enrolled between 1995-1997. None of the subjects had a history of heart attack.
Once again, the team assessed the participants' self-reported drinking habits and monitored their incidence of heart attack up until 2008. During follow-up, 2,966 subjects had a heart attack.
Compared with non-drinkers and rare drinkers, those who consumed three to five drinks a week had the lowest heart attack risk, with the risk reducing by around 28% with every additional drink consumed, up to five drinks.
However, the researchers note that they did observe an increased risk of death from certain forms of cardiovascular disease with the consumption of at least five drinks weekly, and high alcohol consumption was also linked to greater risk of death from liver disease.
As such, the authors recommend against high alcohol intake and stress that their findings do not suggest people should take up frequent drinking in order to improve their heart health.
"I'm not encouraging people to drink alcohol all the time. We've only been studying the heart, and it's important to emphasize that a little alcohol every day can be healthy for the heart. But that doesn't mean it's necessary to drink alcohol every day to have a healthy heart."
But for those who do like to indulge in a drink, Janszky recommends that it is best to consume "moderate amounts relatively often," noting that drinking larger amounts in one sitting can raise blood pressure.
Study strengths and limitations
While these studies are not the first to associate moderate drinking with better heart health, the team says they may be more accurate, noting that previous studies have looked at such associations among populations in which alcohol consumption is very common.
In Norway, however, drinking is not as popular. In the second study looking at the association between alcohol consumption and heart attack risk, for example, 41% of participants reported that they did not drink at all or only consumed less than half an alcoholic drink weekly.
"The relationship between alcohol and heart health has been studied in many countries, including the USA and southern European nations," says Janszky. "The conclusions have been the same, but the drinking patterns in these countries are very different than in Norway. In countries like France and Italy, very few people don't drink."
"It raises the question as to whether earlier findings can be fully trusted, if other factors related to non-drinkers might have influenced research results," he adds. "It may be that these are people who previously had alcohol problems, and who have stopped drinking completely."
There are some limitations to these latest studies, however. For instance, the authors note that the alcohol consumption of participants was self-reported, meaning alcohol intake could have been underestimated.
Contrary to these new findings, research reported by MNT last May suggested that moderate drinking may increase the risk of heart damage for elderly women.