Alcohol may increase breast cancer risk, but is it good for your heart?
Before you reach for a glass, we look behind the headlines to find out if alcohol really could boost your heart health.
Having one or two more alcoholic drinks a day could lead to a lower risk of coronary heart disease and a higher risk of breast cancer among post-menopausal women, new research has suggested.
The research, published in the BMJ, looked at 22,000 post-menopausal women in Denmark who had taken part in a research study that took place between 1993-98, with a second examination about five years later in 1999-2003.
The study showed that women who increased their alcohol intake over a five year period had a lower risk of coronary heart disease, but a higher risk of breast cancer, than women with a stable high intake.
However while 22,000 women were included in the study, only 1,955 of them increased their intake by seven or more alcoholic drinks a week. So the statement that drinking one or two more alcoholic drinks a week leads to a lower risk of CHD applies to less than 2,000 women in the study, not the full 22,000.
Researchers from the University of Southern Denmark concluded that alcohol could bring down the risk of heart disease by raising levels of ‘good’ cholesterol.
They also suggested that there was no significant association with the risk of CHD and lowering alcohol intake over the five years.
The BHF View
Drinking more than a recommended amount can have a harmful effect on your health, there are safer and healthier ways to protect your heart
Senior Cardiac Nurse
June Davison, Senior Cardiac Nurse at the British Heart Foundation said: “Although previous research has identified that low-moderate intakes of alcohol is associated with decreased risk of coronary heart disease, the benefits of drinking alcohol can be outweighed by an increased risk of other health problems.
"Drinking more than a recommended amount can have harmful effect on your health, such as increasing the risk of some cancers and there are safer and healthier ways to protect your heart, such as not smoking, being active and eating a healthy balanced diet.
"At the BHF, we would always recommend that if you drink alcohol it is important to keep within the guidelines: men and women should not drink more than 14 units of alcohol each week and you should have several alcohol-free days each week, whether you drink regularly, or only occasionally.”
Limitations of the research
The study covered a large number of women, but they were aged 50-64 and postmenopausal, so their findings cannot be generalised to younger or older people, or pre-menopausal women.
Another limitation was the fact that alcohol intake was self-reported and possibly underestimated, although the method is generally assumed to be valid.
While the study does give an average (median) amount drunk (which was 5.4 drinks a week in the first examination and 4.8 drinks a week in the second examination), this would vary between individuals and we don't know how much those who increased their intake were drinking.
Similarly, the drinking patterns were not taken into account. Studies have shown that binge drinking has an adverse effect on coronary heart disease and can lead to an increased risk of death.
The story was covered in the UK by The Telegraph and Daily Mail.
A flaw in the media coverage is that it mentions that a glass or two of wine could be good for you, but doesn’t explain that this means a small rather than standard-sized glass.
One unit contains 8g of ethanol, but the study classed a drink as 12g of ethanol, which is the equivalent of a small glass of wine (1.5 units) and less than a pint of medium strength beer (2 units).
The Daily Mail’s headline was ‘Beer or wine ‘could be good for your heart’: Glass or two a night found to reduce the risk of heart disease by up to a fifth’. The researchers concluded that the findings support that alcohol is associated with an increased risk of breast cancer and a lower risk of coronary heart disease. However, this headline could not be applied to a large number of readers. If people who were reading the article were not female, aged between 50-64, and postmenopausal then this research cannot reliably be applied to them.