Researchers suggest they may be able to explain why moderate drinking is good for the heart because, contrary to what was previously believed, it acts on the brain rather than the blood as was once supposed.
However, because alcohol also increases the risk of cancer at any level, according to researchers, they don’t advise people to drink. Understanding this mechanism may instead suggest better approaches to obtaining the same effect, for as through meditation or exercise.
Large epidemiological studies have demonstrated for decades that those who drink moderately—less than one drink per day for women and one to two drinks per day for men—had reduced chances of serious cardiovascular events like heart attacks and strokes than those who drink more.
However, scientists have never been able to pinpoint the precise reason why this is the case. Drinkers have lower levels of a sticky protein called fibrinogen in their blood, which may minimize the risk of severe clots. Alcohol also appears to enhance levels of HDL, the “good” cholesterol. Additionally, alcohol may improve insulin sensitivity in small doses. But it seems like these don’t adequately communicate the benefit.
So a group of cardiologists in Boston decided to turn their attention to the brain.
Senior author of the study and co-director of the Cardiovascular Imaging Research Center at Massachusetts General Hospital, Dr. Ahmed Tawakol, observed that after consuming a small amount of alcohol, you feel relaxed before you become drunk.
“If you think of short-term alcohol, the first effect that people get … is a little bit of a destressing response,” he said.
“We found that the brain changes in light to moderate drinkers explained a significant portion of the protective cardiac effects,” Tawakol said.
The benefits were especially prevalent among people with a history of anxiety.
“Alcohol was twice as effective at reducing major adverse cardiac events among individuals with stress and anxiety,” Tawakol said. “It was about 20% in most patients but 40% relative risk reduction among individuals with prior anxiety.”