Researchers from Cambridge University and University College London investigated the link between alcohol consumption and 12 cardiovascular diseases by analysing electronic health records of 1.93 million healthy British adults. The participants were free from cardiovascular disease at the start of the study, and non-drinkers were separated from former and occasional drinkers to provide additional clarity.
After accounting for several influencing factors, moderate drinking was found to be associated with a lower risk of first presenting to a doctor with several, but not all, cardiovascular conditions, including angina, heart failure and ischemic stroke, compared with abstaining from alcohol all together.
Previous studies have already suggested that wine and other alcohol have a positive effect on the levels of good cholesterol in the blood and proteins associated with blood clotting and benefit to the heart.
As has become a norm in recent years for such studies, researchers warn that it would be unwise to encourage people to take up drinking as a means of lowering their cardiovascular risk over safer and more effective ways, such as increasing physical activity and stopping smoking.
Dr James Nicholls, Director of Research and Policy Development at Alcohol Research UK, said: “This large-scale study provides strong evidence that the so-called ‘J-curve’ exists: meaning that, in most cases, moderate drinkers are less likely to suffer a heart condition than either heavy drinkers or people who don’t drink at all.’ Moderate drinking is define as a maximum of 14 units of wine or any other alcoholic drink in a week. A small glass of wine (125 mL) translating into 6 glasses/ standard bottle of 750 mL, with an alcohol content of 12% by volume, constitutes 1.5 units; this would mean 8 glasses per week- to be adjusted for higher alcohol in a majority of wines.
“While the findings provide convincing evidence for protective effects, the authors sensibly point out that this doesn’t mean it would be wise to take up drinking in order to lengthen one’s life – not least because any protective effects tend to be cancelled out by even occasional bouts of heavier drinking,” he said.
Dr Steven Bell, a genetic epidemiologist at Cambridge University, said: "This is an observational study, so no firm conclusions can be drawn about cause and effect." He said it was the first time the association has been investigated on such a large scale and their findings have implications for patient counselling, public health communication, and disease prediction tools.
The authors also cautioned that this did not mean they were less likely to experience a heart attack in future, just that they were less likely to present these conditions at first diagnosis, compared with moderate drinkers.
Dr. Kenneth Mukamal, Associate Professor of medicine at Harvard Medical School in the US, said the study 'does not offer a materially new view of the associations between alcohol consumed within recommended limits and risk of cardiovascular disease'. He added, "This work, however, sets the stage for larger and more sophisticated studies that might harness the huge data into useful, reliable, and unbiased findings,"