A review published recently in Addiction supports a causal link between alcohol consumption and the development of cancers at seven sites: colon, female breast, larynx, liver, esophagus, oropharynx and rectum.
A causal association signifies that there is evidence that the consumption of alcohol directly causes cancer, as opposed to an association that alludes to there simply being some kind of relationship between the two variables. This study provides a more weighted statement than the previously long-recognized association between cancer and alcohol.
Evidence for a dose–response relationship, partial reversal of risk when consumption is reduced, statistical adjustment for other variables that may be responsible for the association, and specificity of the association with specific cancers all supported this causal link.
Epidemiological data that lead to these conclusions were derived from reviews completed in the last 10 years by the World Cancer Research Fund and American Institute for Cancer Research, the International Agency for Research on Cancer, the Global Burden of Disease Alcohol Group and the latest comprehensive meta-analysis by Vincenzo Bagnardi (Università degli Studi di Milano-Bicocca, Italy) and colleagues, which builds on previous meta-analyses of the effects of consumption of alcohol on individual cancers.
The review cites further data indicating that alcohol led to approximately 500,000 deaths from cancers in 2012, which corresponds to 5.8% of worldwide cancer deaths. Although the highest risks are linked with the heaviest drinkers, low to moderate consumers also experience a notable burden.
The review additionally weakens current evidence that suggests moderate drinking provides protection against cardiovascular disease.