Alcohol, Labeling, and the Future of Dietary Guidance

The International Agency for Research on Cancer classifies alcohol as a Group 1 carcinogen, with convincing evidence linking its consumption to cancers of the breast, liver, colorectum, esophagus, and mouth and throat, and this cancer risk appears to rise with intake in a dose-dependent way without a clearly established safe lower threshold. For decades, observational studies suggested a "J-shaped curve" in which light-to-moderate drinkers showed somewhat lower cardiovascular risk than both heavy drinkers and complete abstainers, but this apparent benefit has come under sustained scrutiny: more recent studies using Mendelian randomization, along with re-analyses that address the so-called "sick quitter" effect, in which abstainer comparison groups include former heavy drinkers with pre-existing health problems, suggest that much or all of the apparent protective association reflects confounding by the generally healthier lifestyles of moderate drinkers rather than a genuine protective effect of alcohol itself. In 2023 the WHO issued a statement that no level of alcohol consumption can be considered safe for health, and several national guidelines, including a substantially revised 2023 guidance in Canada, have lowered their recommended consumption limits accordingly.