For drinkers over 50, possible benefits of moderate drinking may outweigh the risk of developing certain cancers
Numerous studies have highlighted a link between alcohol abuse and the risk of developing cancer in general. However, the evidence is conflicting when it comes to moderate consumption, the beverage types and the risk of various cancer types.
A prospective study including 124 193 people (Kaiser Permanente population), was conducted between 1978 and 2012. The results highlight a higher risk for heavy drinkers (more than three drinks/day) to develop cancer of the upper airway/digestive system, lung, colorectal, female breast cancer and melanoma (skin cancer). No significant differences according to type of alcoholic beverage were observed.
The study also found that under-reporting of alcoholic beverages strongly affected the cancer risk and thus, for moderate drinkers (up to two drinks/day), no definite conclusion could be drawn about the cancer risk. However, the authors state: “At present, a possible increased cancer risk at moderate intake should enter the individual estimation of the overall risk-benefit equation for alcohol drinking, especially for young people. For most individuals older than 50 years, the overall benefits of moderate drinking, especially the reduced risk of athero-thrombotic disease, outweigh possible cancer risk”
Klatsky AL, Li Y, Tran HN, Baer D, Udaltsova N, Armstrong MA, Friedman GD. Alcohol Intake, Beverage Choice, and Cancer: A Cohort Study in a Large Kaiser Permanente Population. Perm J 2015;19:March 1, 2015. http//dx.doi.org/10.7812/TPP/14-189
For more information about this article, read the scientific abstract here.
Editorial note:
There is no doubt that heavy drinking leads to certain cancers and many adverse and societal problems, however, as it is evident from the study above and other research, it is difficult to judge the effects of light-to moderate drinking and, as the authors of this study did, it is important to evaluate the net health effects of alcoholic beverage consumption.
Relating alcoholic beverages to the risk of cancer, there are some general problems to consider:
- In the epidemiological data provided, the intake of alcoholic beverages is usually under-reported by subjects (which could exaggerate the harm associated with light drinking).
- In most studies, the pattern of drinking (regularly and moderately vs. binge drinking with a similar total weekly alcohol consumption) as well as beverage type have generally not been taken into account. However, this aspect of drinking pattern is important given that binge drinking is associated with much higher blood alcohol concentrations and acetaldehyde accumulation (a known carcinogen) and production of free radicals (reactive oxygen species). Considering that the blood alcohol level may be the most important mechanism for effects on cancer risk, the pattern by which an individual consumes a given amount of alcohol is particularly relevant in interpreting associations.
- In addition, epidemiological studies usually provide data only for a short period of time, while the development of cancer may relate to exposures over many decades; it takes a long time for cancer to develop.
- Cancer is multi-factorial, so it is impossible to say that cancer is due to one single factor. It can be due to genetic, environmental, lifestyle (ie. Smoking, diet) and a number of other factors.
For a more detailed discussion on the association between alcohol consumption and cancer among leading scientists, please see:
More information about problems with under-reporting: Klatsky AL, Udaltsova N, Li Y, Baer D, Tran HN, Friedman GD. Moderate alcohol intake and cancer: the role of underreporting. Cancer Causes Control 2014; on-line publication; DOI 10.1007/s10552-014-0372-8 2014. https://www.wineinformationcouncil.com/index.php?option=com_k2&view=item&id=1807:underreporting-of-alcoholic-beverages-consumption-affects-the-relation-of-alcohol-to-the-risk-of-cancer&Itemid=640