Canada’s Guidance on Alcohol and Health: Final Report – A critique by the International Scientific Forum on Alcohol Research (ISFAR)

In January this year, the Canadian Centre on Substance Use and Addiction (CCSA) issued its recommendations entitled: Canada’s Guidance on Alcohol and Health: Final Report1. The Final Report contains three documents produced for three different target groups, namely one public summary for the general public, a technical summary for health professionals and a technical report for alcohol scientists. The public summary, entitled “drinking less is better” and subtitled “we know that even a small amount of alcohol can be damaging” states that science is evolving so that recommendations about alcohol need to change and that even a small amount of alcohol is damaging to everyone.
The recently issued Canada’s Guidance on Alcohol and Health by the CCSA focuses primarily on risk of death estimated by modelling twenty-one disease-alcohol consumption associations. The scientific evidence relating to both abusive and moderate alcohol consumption is itself not sufficiently consistent to produce precise recommendations for safe drinking for every alcohol consumer. There is no clear scientific evidence that uniformly applies to all population groups.
The accompanying Final Report suggests that “evidence has changed since the release of the 2011 Canadian Low Risk Drinking Guidelines”. This evidence includes the relationship between alcohol and cancer per se, stating that there is now no lower risk threshold for alcohol consumption; this contradicts 2022 data from 142,960 individuals from the population-based study MORGAM Project, that shows that there is indeed a nadir of the association. The authors also state that there is now no lower risk threshold for hypertension which was not shown in the reference that was used in the mathematical risk modelling. Additionally, they state that the potential cardioprotective effect of light to moderate alcohol consumption is more uncertain than previously estimated, which again was not shown in the reference selectively cited; this reference actually highlighted that relevance of drinking pattern in mathematical modelling. Other recent references cited are also considered contentious. This is not new data since 2011.
Forum members consider it a major omission not to take into account the association of alcohol consumption with overall mortality and only base their guidelines on an internationally criticised model. Moreover, the model mainly used evidence of low to very low quality. The authors also chose not to differentiate between gender and downplayed the reduced risk of cardiovascular disease and some other diseases like type II diabetes mellitus, nor did the authors take underreporting into account. Further, the authors neglected drinking pattern in their modelling which impacts risk of both short- and long-term alcohol-related harms and more importantly differentiates protective from harmful levels of alcohol consumption. The Forum also noticed several cases of misinterpretation of the input used for their modelling. Interestingly while these significant limitations were listed in the accompanying technical report, they were completely ignored in generating the long-term risk estimates for death and disability for Canadian alcohol consumers. In addition, the Forum noted that members of the Low-Risk Alcohol Drinking Guidelines Scientific Expert Panels and their associates are also authors of regularly cited references in the accompanying Final Report, certain of which are contentious and consistently use now widely debunked arguments around the ‘sick quitter’ hypothesis.
Accordingly, the Forum believes that these recommended guidelines do not contribute to their own intention to allow Canadians to make well-informed decisions on alcohol use and how it will affect their health. Furthermore, the evidence base assessing all-cause mortality and the risk of mortality from any cause at the 2011 alcohol level of 134.5 g/week for women, with no more than 27 g/day most days and 202 g/week for men, with no more than 40 g/day most days, remains robust and the hence the 2011 guidelines remain relevant to Canadians rather than the 2023 CCSA recommendations.
A detailed critique of this paper by the International Scientific Forum on Alcohol Research, is available on alcoholresearchforum.org/critique-261/