Drinking one bottle of wine a week is associated with the same lifetime cancer risk as smoking five cigarettes a week for men, and 10 cigarettes for women, according to a new study.

The study calculates alcohol cancer risk in cigarette equivalents and may help communicate the links between moderate levels of alcohol and cancer, and raise public awareness of alcohol-associated cancer risks, according to a study published in the open access journal BMC Public Health.

Professor Mark Bellis of the College of Human Sciences at Bangor University who has been involved in the research said: “For many years clear health messages on every advert for cigarettes and every packet sold made the public aware that they are a major cause of cancer. We are yet to see any equivalent for alcohol, so most people drink with little or no knowledge about its cancer-causing effects.

“Many people may be surprised that a woman drinking about half a bottle of wine each night carries a similar cancer risk to one with a smoking habit of 23 cigarettes per week.

“We hope that by expressing the risks of cancer from alcohol in terms of cigarettes smoked this will act as a simple but effective method to make sure people are better informed about the cancer risks associated with the drinks they are sold.”

Dr Theresa Hydes, the corresponding research author said: “Our study describes the percentage increase of the risk of cancer within the UK population associated with different levels of alcohol consumption, and is the only study to provide a ‘cigarette equivalent’ in terms of harm.

“We aimed to answer the question: Purely in terms of cancer risk – that is, looking at cancer in isolation from other harms – how many cigarettes are there in a bottle of wine? Our findings suggest that the ‘cigarette equivalent’ of a bottle of wine is five cigarettes for men and ten for women per week.”

The authors estimate that in non-smoking men, the absolute lifetime risk of cancer – that is, the risk of developing cancer during one’s lifetime – associated with drinking one bottle of wine per week is 1.0%. For women, it is 1.4%. Thus, if 1,000 men and 1,000 women each drank one bottle of wine per week, around ten extra men and 14 extra women may develop cancer at some point in their life.

In men, this risk appears to be associated primarily with cancers of the gastrointestinal tract, whereas in women, 55% of cases appear to be associated with breast cancer. The study aims to draw the public’s attention to the fact that just moderate levels of drinking, e.g. one bottle of wine per week can put people at risk of cancer, particularly breast cancer.

The study aims to draw the public’s attention to the fact that just moderate levels of drinking, e.g. one bottle of wine per week can put people at risk of cancer, particularly breast cancer. The authors highlight that this in an important issue as breast cancer is the most commonly occurring cancer in women in the UK.

The authors also found that drinking three bottles of wine per week (approximately half a bottle per day) – a level known to increase the risks of a wide range of different health problems – was associated with an increase of absolute lifetime cancer risk to 1.9% in men and 3.6% in women, or 19 in 1,000 men and 36 in 1,000 women, respectively. This is equivalent to smoking roughly eight cigarettes per week for men and 23 cigarettes per week for women.

Dr Hydes said: “We must be absolutely clear that this study is not saying that drinking alcohol in moderation is in any way equivalent to smoking. Our finds relate to lifetime risk across the population. At an individual level, cancer risk represented by drinking or smoking will vary and for many individuals, the impact of ten units of alcohol (one bottle of wine) or five to ten cigarettes may be very different.

“Our estimation of a cigarette equivalent for alcohol provides a useful measure for communicating possible cancer risks that exploits successful historical messaging on smoking. It is well established that heavy drinking is linked to cancer of the mouth, throat, voice box, gullet, bowel, liver and breast. Yet, in contrast to smoking, this is not widely understood by the public. We hope that by using cigarettes as the comparator we could communicate this message more effectively to help individuals make more informed lifestyle choices.”