Alcohol in moderation ‘could lower stress-related risk of heart disease’
A study by American scientists has explained why light-to-moderate alcohol consumption could lower the risk of heart disease.
The scientists, who published their findings in the Journal of the American College of Cardiology,discovered that alcohol in moderate quantities was associated with long-term reductions in stress signalling in the brain.
As a result, the positive impact on stress in the brain appeared to account for the reduction in cardiovascular events in people who are light to moderate drinkers.
Previous studies had suggested that one or two drinks per day was associated with a lower risk of cardiovascular disease, but it was not known how alcohol had specific benefits.
The study, which included more than 50,000 individuals, concluded that light to moderate drinkers were associated with a “substantial reduction” in risk of cardiovascular disease, even when adjusting for other factors such as genetic, lifestyle and socio-economic factors.
A sub-set of 754 individuals who had previously undergone brain imaging were then assessed to determine the effect of light-to-moderate alcohol consumption.The brain imaging showed reduced stress signalling in the amygdala — the brain area associated with stress responses.
Investigators also looked at whether moderate consumption would be even more effective at reducing heart attacks and strokes in people who are prone to a chronically higher stress response, such as those with a history of significant anxiety.
They found that, within the 50,000-patient sample, light-to-moderate drinking was associated with nearly double the cardiac-protective effect in individuals with a history of anxiety, compared with others.
But the study also showed any alcohol consumed increased the risk of cancer and at higher amounts – more than 14 drinks a week – heart attack risk increased while brain activity decreased.
Speaking about the findings, senior author and cardiologist Ahmed Tawakol, MD, co-director of the Cardiovascular Imaging Research Center at Massachusetts General Hospital, said: “We found that the brain changes in light to moderate drinkers explained a significant portion of the protective cardiac effects.
“When the amygdala is too alert and vigilant, the sympathetic nervous system is heightened, which drives up blood pressure and increases heart rate, and triggers the release of inflammatory cells.
“If the stress is chronic, the result is hypertension, increased inflammation, and a substantial risk of obesity, diabetes, and cardiovascular disease.”