A drink or two a day isn’t thought to be particularly harmful, at least according to some guidelines on alcohol consumption. Some studies even indicate that a moderate level of drinking may benefit heart health and the CDC recommends that men have no more than two drinks per day, and women no more than one. But a new study of over 350,000 people has found that even drinking a small amount of alcohol increases the risk of cardiovascular disease.
The huge U.K. Biobank study published in the journal Clinical Nutrition involved data collection from 22 centers across the U.K. and looked at 333,259 people who consumed alcohol and 21,710 who didn’t, following them for an average of 7 years to monitor their health and alcohol consumption. The people were aged between 40 and 69.
For studies of this type, people who drink are often compared to people who have never drunk alcohol to find out whether there are differences in their health. But the study demonstrated that making this comparison can be very misleading as some never drinkers avoid alcohol due to other health conditions. In their reference group of over 20,000 “never drinkers” there were higher rates of most chronic diseases than in the group of people who drank. So when they compared the drinkers to this group, it appeared that the drinkers were less likely to experience cardiovascular events.
“Biases embedded in epidemiological evidence mask or underestimate the hazards associated with alcohol consumption. When these biases are accounted for, the adverse effects of even low-level alcohol consumption are revealed,” said Rudolph Schutte, PhD, associate professor at Anglia Ruskin University in the U.K. and first author of the study.
To fix this, the researchers grouped people based on how much they drank and compared these groups, finding that those who drank more experienced more deaths from heart disease. This held true for drinkers of beer, cider and spirits but when the researchers separated out wine drinkers, they actually found a slightly lower chance of a particular type of disease called coronary artery disease, but not other types of cardiovascular disease.
The study also found that even people who drink a low to moderate amount of alcohol (less than 14 units per week as recommended in the U.K.) are still at higher risk of cardiovascular issues.
“Among drinkers of beer, cider and spirits in particular, even those consuming under 14 units a week had an increased risk of ending up in hospital through a cardiovascular event involving the heart or the blood vessels,” said Schutte.
The researchers conclude that any future studies should take into account that never-drinkers often have health conditions which contribute to their decision.