Advice whether alcohol can protect against coronary heart disease can be confusing.
To debunk the myths and find out the facts, we talked to two medical experts: Professor Paul Wallace, Drinkaware’s Chief Medical Adviser, and Professor Jonathan Chick, Medical Director of Castle Craig Hospital and Editor-in-Chief of the journal Alcohol and Alcoholism.
They agree that, where alcohol and the heart are concerned, drinking within the UK Chief Medical Officers’ low-risk guidelines of no more than 14 units per week is key.
A large study, published in March 2017, found that drinking less than 21 units per week for men and less than 14 units for women was associated with a lower risk of initial presentation of the common cardiovascular diseases1. Although for most people moderate drinking had a small protective effect on the heart, this can be outweighed for some people by increased risks of other harmful health effects:
- A review of evidence carried out on behalf of the UK’s Chief Medical Officers concluded that women over 55 are the only group that may experience some overall protective effect from drinking a small amount of alcohol (around 5 units per week)2.
- Beyond the low-risk alcohol guidelines, alcohol’s potential benefits on the heart are outweighed by other health risks, including acute harms and other illnesses, such as liver disease and cancer. The potential benefit only occurs if your 14 units is spaced out during the week – consuming heavily in one session can cause a heart attack – sometimes called ‘holiday heart’3.
- Any potential benefits on the heart depend both on your overall consumption and your general pattern of drinking (how much and how often).
So what do we know about how alcohol might produce its beneficial effects on the heart? Illnesses due to damage to arteries, such as the coronary arteries that nourish the heart, mainly affect people of middle age and older. Scientists believe that there are two main mechanisms by which small amounts of alcohol can have a protective effect as one enters the age where heart disease commonly occurs.
The first, explains Professor Wallace, is that alcohol appears to affect the levels of cholesterol circulating in the blood, reducing the amount of fatty deposit (atheroma) which narrows our arteries and makes them more likely to clog. Secondly, alcohol can help prevent the formation of blood clots which can close off the arteries, causing a heart attack. It can stop platelets from clumping together to form clots. A small amount of alcohol with a meal can also reduce the sudden rise of a protein (fibrinogen) produced by the liver which can increase the likelihood of blood clots forming – thrombosis.
Wine drinkers would like to believe that the old adage that red wine is good for the heart is true. But, is it? “Antioxidants in general help to prevent thrombosis and it is true red wine has a relatively high concentration of antioxidant substances called flavonoids. White alcoholic drinks, like vodka and cider, contain the least concentration of flavonoids. But this is a subject where more research is needed before we can give specific advice,” says Professor Chick. Though some studies found wine to have protective effects, it may be because wine drinking is more often linked to meals than beers and spirits
Professor Wallace agrees that this commonly held belief about red wine is debatable. "It is the alcohol content that causes this small protective effect which is also found with other alcoholic drinks, such as beer and spirits,” he says. “I do worry that some people have actually got the wrong end of the stick and think: ‘I am drinking red wine and that’s okay because it is good for my heart.’”
There is evidence from studies that if you’ve had a heart attack, your survival prospects may be slightly better if you drink moderately but people who don’t usually drink alcohol are not advised to start doing so to protect themselves against heart disease. The evidence for the benefits does not justify this. “There are much better ways to change your lifestyle to reduce your risk of heart disease, like stopping smoking, taking more exercise and eating a healthier diet, which don’t carry risk,” says Professor Wallace.
Professor Wallace and Professor Chick both conclude that although there is evidence to suggest that moderate drinking (i.e., within the CMOs’ low-risk unit guidelines) can protect against coronary heart disease, drinkers must be aware that even low-level drinking also increases the risks of other illnesses such as alcohol-related liver disease and cancer. So the best way to protect your heart is by adopting a healthy lifestyle.
“A healthy diet, taking regular exercise, stopping smoking – you should try these things before thinking about using alcohol as a protector against coronary heart disease, because alcohol can make other problems for you,” says Professor Wallace. “For the facts, read information on the Drinkaware or British Heart Foundation websites.”
We have a lot of evidence about alcohol and the heart,” concludes Professor Wallace. “When new studies hit the headlines lauding the health benefits of drinking, although it may be tempting to simply believe it, my advice is to think it through carefully and listen to expert assessments.”