Alcohol and Cancer

If we were to randomly pick a number of people off the street and ask for their views about the effects of drinking alcohol, we would almost certainly be told that it is mainly a good thing. Its abuse would be decried but, generally speaking, alcohol is likely to be seen as a fairly pleasant and innocuous substance if consumed “in moderation”, with possible beneficial effects on “the heart” and “blood circulation” – as snippets and articles in the print media frequently point out.  So the final judgment of the man in the street would quite likely be that, on the whole, alcohol in regular amounts tends to have a beneficial effect on health.

But would science agree? What does it really have to say about alcohol and its effect on the human body?

While the true connection between alcohol and cardiovascular health merits greater in-depth analysis – many studies are now questioning the once-cherished belief that a drink or two a day will reduce the chances of a heart attack or stroke - recent and not-so-recent studies have revealed a sinister link between alcohol and cancer.

That there is a connection between even low levels of alcohol consumption and breast cancer has been known for decades. Even the supposedly ‘safe’ limits enthusiastically promoted for many years by health authorities and agencies all over Europe came with a proviso that they were not valid for women with a family or personal history of breast cancer. Even small amounts say, one drink per day, were known to be linked with a greater chance of contracting breast cancer. Other than that, however, little mention was made of the mounting evidence that alcohol is heavily implicated in several other types of cancer.

Cancer is the second most important cause of death in the EU; some 2.5 million people are diagnosed with this condition in the region each year (http://ec.europa.eu/health/major_chronic_diseases/diseases/cancer/). Amongst people aged 15-64 years living in the EU in 2004, 8% of all male and 6% of all female cancer deaths were attributable to alcohol. (http://ec.europa.eu/health/alcohol/docs/ev_20120418_co07_en.pdf.

 According to the International Agency for Research on Cancer (IARC) of the World Health Organisation (WHO), alcohol is a causal agent for cancers of the mouth, pharynx, larynx, oesophagus, liver, colorectum and breast (http://www.iarc.fr/en/media-centre/pr/2009/pdfs/pr196_E.pdf ). Note the term “causal”: it is not simply a question of a correlation between alcohol consumption and cancer. In a considerable number of cases, cancer is the consequence of the decision to drink alcohol.

There is a dose-response relationship between cancer risk and alcohol consumption, that is to say, the more one drinks the greater the possibility that one will contract the condition. A seminal study carried out by Corrao and his colleagues in 2004 showed that the relative risk for cancer increases according to amount drunk daily. Compared to non-drinkers, those who drink 20 grams of alcohol every day experience a 19% increase in risk for liver cancer, 25% for breast cancer, 39% for oesophageal cancer, 43% for cancer of the larynx and 86% for cancers of the mouth and pharynx (http://www.cancercare.ns.ca/site-cc/media/cancercare/alcohol%20in%20canada.pdf ). If one partakes of four alcoholic drinks (40 grams) a day, one at least doubles the risk in practically every case. If one smokes as well as drinks the chances of contracting some cancers can be said to soar.

Translating the above into more meaningful equivalents, drinks in Malta are assumed to contain 8-10 grams of absolute alcohol. Therefore 20 grams would be roughly equivalent to 2 half-pint bottles of local beer, 2 bar tots of spirits or 2 small glasses of wine.

There does not seem to be a drinking threshold below which one may drink safe in the knowledge that the alcohol consumed will not raise one’s cancer risk. Small amounts will raise the possibilities one will incur cancer. So, in so far as cancer risk is concerned, it appears that the safest advice health authorities can give is to drink no alcohol. This is what, for example, the World Cancer Research Foundation (WCRF) recommends (http://www.wcrf-uk.org/cancer_prevention/recommendations/alcohol_and_cancer.php). 

However, given that it is still unclear whether alcohol has a cardio-protective effect or not, there are those who would still maintain that light drinking will not have a net negative effect on health. According to this line of reasoning, light drinking would, as it were, compensate for the increased cancer risk by decreasing the chances of cardiac problems. The WHO itself believes there is evidence that half a drink (5 grams) a day will indeed protect middle-aged persons against the risk of a heart-attack but, mindful of the other risks the consumption of alcohol can carry, WHO advises that we would be better off stopping smoking, losing weight and exercising rather than drinking even small amounts

(http://www.euro.who.int/__data/assets/pdf_file/0003/160680/e96457.pdf).

It therefore appears that, in terms of cancer prevention, we would be best off not drinking any alcohol at all. If, for some reason, we decide we do wish to drink we should make sure we drink as little and as infrequently as possible. The old slogan used by the WHO - “Less is better’’ - in conjunction with its advice on alcohol use seems to be particularly apt in this context.