The surprising side effect drinking alcohol has on your heart (and brain)

Thinking about skipping happy hour? This new study will make you reconsider it.

According to new findings presented at the ACC’s 70th Annual Scientific Session, moderate intake of alcohol can dramatically decrease one’s risk for developing cardiovascular disease.

Alcohol calms your brain?

It all has to do with alcohol’s impact on stress levels in the brain.

The researchers from the American College of Cardiology behind the latest report based their analysis on the 53,064 participants featured in the Mass General Brigham Biobank health care survey.

Each participant underwent standard health monitoring; including 18F-fluorodeoxyglucose positron emission tomography, (PET imaging) meant to gauge brain activity related to fear and stress in the amygdala.

Those who drank moderately (no more than one drink per day for women and no more than two drinks per day for men) evidenced comparable effects as exercising with respect to decreased stress in their brain, which in turn decreased their risk for experiencing heart disease and stroke.

The authors make a point to note that the beneficial outcomes indexed in their new study were less about alcohol itself and more about its effect on regions of the brain linked to cardiovascular health.

“We found that stress-related activity in the brain was higher in non-drinkers when compared with people who drank moderately, while people who drank excessively (more than 14 drinks per week) had the highest level of stress-related brain activity,” explains Dr. Kenechukwu Mezue, who is a fellow in nuclear cardiology at Massachusetts General Hospital, in a media release. “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.”

By the end of the study period, 7,905 participants (15%) reported a major cardiovascular event. Seventeen percent of these belonged to the low alcohol consumption group (less than one drink per week). Meanwhile, only 13% of members belonging to the moderate drinking group, (those who had between one and 14 drinks a week) reported a cardiovascular event before the end of the study period.

Moreover, moderate drinkers demonstrated a 20% lower risk of experiencing a major cardiac event in comparison to low or non-drinkers. PET scans also revealed that this cohort had lower stress-related brain activity.

“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. 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,” Mezue continues.

“The current study suggests that moderate alcohol intake beneficially impacts the brain-heart connection. However, alcohol has several important side effects, including an increased risk of cancer, liver damage, and dependence, so other interventions with better side effect profiles that beneficially impact brain-heart pathways are needed,” Mezue warns.

Drinking more than the guideline established by the authors and US health systems can produce the opposite effect as those enjoyed by moderate drinkers.