Alcohol and Cancer Risk

Neither trivialize nor terrorize

The subject of alcohol and cancer risk is particularly charged, because of the fear that the disease still evokes and the strong emotions it arouses. That is why “Alcohol and Cancer Risk,” the latest Éduc’alcool report in the Alcohol and Health series, tackles the topic with nuance and scientific discipline.

Drinking alcohol leads to a significant increase in the risk of cancers of the mouth (including the oral cavity and pharynx), the esophagus and the larynx, and there is a moderate increase in the risk of cancers of the liver, colon, rectum and female breast.

The report confirms that alcohol increases the risk of seven kinds of cancer, but the risk is relative and affects different people differently, depending on a number of variables. Of course, health is a complex matter that cannot be reduced to a single concern about whether or not one is likely to develop cancer. However, for those who are concerned solely about cancer prevention, it is recommended that drinking be reduced as much as possible. For everyone else, following the low-risk drinking guidelines remains a very reasonable choice. As Éduc’alcool has been saying for years, moderation is always in good taste.

It’s a fact that nearly one in two Quebecers will be affected by cancer at some point during their lifetime, and that many myths about cancer are still widely believed. It is therefore extremely important to provide comprehensive, serious and solidly founded information about the relationship between alcohol and cancer risk. Furthermore, the information must be presented calmly, it must distinguish relative risk from absolute risk, and it must neither trivialize nor terrorize.

The Éduc’alcool report also shows the risk of developing certain types of cancer based on amount of alcohol consumed. It explains the biological mechanisms triggered by alcohol, which affect cancer risk. It also discusses a number of risk factors that can intensify the link between alcohol and cancer, and covers the effect of alcohol on cancer risk according to drinking profile. The report was reviewed by Dr. Philippe Sauthier, of the Centre intégré de cancérologie and director of the Quebec Cancer Foundation, which is partnering with Éduc’alcool for the distribution of the report.

There were 206,200 new cases of cancer and 80,800 deaths caused by the disease in Canada in 2017. It is estimated that alcohol was a factor in 10,310, or 5%, of the new cancer cases and 3,636, or 4.5%, of the cancer deaths.

Relative risk and absolute risk

A cautionary note is in order when assessing the true impact of alcohol on cancer. As we know, in science, it is important to distinguish association from causation, and relative risk from absolute risk.

For example, risk increases most dramatically as alcohol use goes up when it comes to cancers of the oral cavity and pharynx. Drinking an average of one glass of alcohol a day increases the risk of death from these cancers by 42%, while having two drinks a day is associated with a 96% increase in risk. However, the risk of death from oral or pharyngeal cancer among men and women under the age of 70 is between 0.2% and 0.5%. These relative increases of 42% and 96% mean the risk for people of actually dying from this type of cancer increases from 0.5 % to 0.71 % if they have one drink a day, and to 0.98% if they have two drinks a day.

Many risk factors

The Éduc’alcool report also points out that the risk of cancer among drinkers varies according to genetic profile. In addition, alcohol appears to interact with a number of external risk factors. And drinking profile is of the utmost importance. In other words, how much people drink, what they drink, and the way they drink are all factors that can affect their health.

Cancer can develop as a result of an interaction between personal genetic factors and a variety of external carcinogens. Therefore, the association between alcohol and cancer risk should be recognized while keeping in mind that cancer is not a disease with a single cause.

Finally, Éduc’alcool notes that any recommendations with regard to drinking and health must be made in light of epidemiological data and evidence for all diseases known to be caused, in part, by alcohol. This obviously includes cancer, but also includes other diseases, such as diabetes, pancreatitis and cardiovascular diseases. With regard to the latter, significant data has shown that, compared those who do not drink any alcohol at all, people who drink excessively increase their risk of coronary disease, but people who drink moderately reduce that risk.