Even light alcohol intake can damage the heart

While previous observational research has suggested that light alcohol consumption may provide heart-related benefits, a large study led by the Massachusetts General Hospital (MGH) has found that alcohol intake at all levels is in fact linked to cardiovascular disease. According to the researchers, any benefits that were observed before most likely resulted from other lifestyle factors common among light to moderate drinkers.

The study included 371,463 adults from the UK Biobank, a large biomedical database containing in-depth genetic and health information about a vast number of UK residents. The participants had an average age of 57 and an average alcohol consumption of 9.2 drinks per week. Consistent with earlier studies, light to moderate drinkers appeared to have the lowest risk of heart disease, followed by people who abstained from drinking completely. As expected, participants who drank heavily had the higher risk of developing cardiovascular issues.

However, the researchers found that light to moderate drinkers often tended to have healthier lifestyles than abstainers, such as more physical activity and vegetable intake, and less smoking. Taking these lifestyle factors into account significantly lowered any supposed benefit associated with light alcohol consumption. 

By conducting advanced genetical analyses of samples taken from the participants, the scientists discovered that individuals with genetic variants that predicted higher alcohol consumption were indeed more likely to consume larger amounts of alcohol and to have hypertension and coronary artery disease. 

The investigations also revealed that there are substantial differences in heart disease risk across the spectrum of alcohol consumption for both genders, with minimal increases in risk when consuming between zero and seven drinks per week, much higher risks when progressing from seven to 14 drinks, and particularly high when consuming over 21 drinks per week.

These findings suggest that the relationship between alcohol intake and cardiovascular risk is an exponential rather than linear one. Thus, while cutting back on alcohol consumption could benefit even people who have just one drink per day, the health gains of reducing alcohol intake are more substantial and clinically meaningful for people who drank more.

“The findings affirm that alcohol intake should not be recommended to improve cardiovascular health; rather, that reducing alcohol intake will likely reduce cardiovascular risk in all individuals, albeit to different extents based on one’s current level of consumption,” concluded senior author Krishna G. Aragam, a cardiologist at MGH. 

The study is published in the journal JAMA Network Open.

—

By Andrei Ionescu, Earth.com Staff Writer