Consuming a moderate amount of alcohol daily can reduce the risk of dying from a major cardiovascular event by up to 20 per cent, scientists reveal.
The researchers have linked moderate alcohol intake – defined as no more than one alcoholic drink for women and two for men per day – with a 20 per cent lower risk of dying from cardiovascular disease (CVD), in a sample of more than 50,000 people.
Interestingly, this percentage decrease was in comparison to people from the sample who had low alcohol intake – defined as less than one drink a week.
The experts, from Harvard Medical School, think it’s likely that moderate alcohol reduces stress signals from the brain.
Scientists at the institution previously made the link between stress in the brain with an increased risk of CVD events like heart disease and stroke.
The study authors stress that they’re not encouraging people to boost their alcohol consumption – but that moderation is the key, just like official guidelines state.
Cheers to that! Alcohol in moderation may help the heart by calming stress signals in the brain, the Harvard Medical School study reveals
‘We found that stress-related activity in the brain was higher in non-drinkers when compared with people who drank moderately,’ said study author Dr Kenechukwu Mezue at Massachusetts General Hospital, the largest teaching hospital of Harvard Medical School.
‘While people who drank excessively (more than 14 drinks per week) had the highest level of stress-related brain activity.
‘The thought is that moderate amounts of alcohol may have effects on the brain that can help you relax, reduce stress levels and, perhaps through these mechanisms, lower the incidence of cardiovascular disease.’
Despite their findings, the research team are actually advocating other, healthier ways of alleviating stress on the brain over alcohol consumption.
They call for new therapies to help lower stress that don’t have the drawbacks of alcohol.
Consumption of any kind of alcohol has been previously linked with weight gain for example, as well as some serious health conditions.
‘Alcohol has several important side effects, including an increased risk of cancer, liver damage and dependence,’ Dr Mezue said.
‘So other interventions with better side effect profiles that beneficially impact brain-heart pathways are needed.’
While the connection between stress and heart disease is widely accepted, the authors said relatively little research had been done on how modifying stress may help protect heart health.
Cardiovascular disease (CVD) is a general term for conditions affecting the heart or blood vessels. CVD events include heart disease and stroke. All heart diseases are cardiovascular diseases, but not all cardiovascular diseases are heart disease (stock image)
To learn more, researchers obtained data from the Mass General Brigham Biobank health care survey of 53,064 participants with an average age of 57.2 years, of whom 59.9 per cent were women.
Alcohol intake, which was self-reported by the participants, was classified as low (less than one drink a week), moderate (one to 14 drinks a week) or high (more than 14 drinks a week).
Major adverse cardiovascular events, including heart attack, stroke or related hospitalisations, were also determined.
Of the patients included, 752 underwent PET scans, which are often used as part of cancer screening but can also show areas in the brain that have increased activity.
The scans allowed researchers to measure activity in regions of the brain known to be associated with stress – the amygdala and the frontal cortex.
They then grouped patients based on the extent of brain stress activity.
Of the 53,064 participants, 7,905 (15 per cent) experienced a major adverse cardiovascular event – 17 per cent in the low alcohol intake group and 13 per cent in the moderate alcohol intake group.
People who reported moderate alcohol intake had not only a 20 per cent lower chance of having a major event compared to low alcohol intake, but also lower stress-related brain activity.
This remained significant even after controlling for demographic variables, cardiovascular risk factors, socioeconomic variables and psychological factors.
‘Previous studies by our group and others have shown a robust association between heightened amygdalar activity and a higher risk of major adverse cardiovascular outcomes, such as heart attack, stroke or death,’ Dr Mezue said.
‘In the current study, path analyses showed that the link between moderate alcohol intake and lowered cardiovascular event risk is significantly mediated though reductions in amygdalar activity.’
The amygdala, shown here in red, is is the centre for emotions, emotional behaviour, and motivation. Humans have two amygdala – one in each temporal lobe of the brain
One of the study’s limitations is that participants self-reported their degree of alcohol intake based on the average consumption of drinks per week.
Future research will focus on determining whether the observed reductions in brain activity are the direct result of moderate alcohol intake, by way of repeated brain scans and more detailed alcohol intake assessments over time.
Dr Mezue is due to present the findings on Monday, May 17 at ACC.21, this year’s annual session from the American College of Cardiology.