spiritsNEWS

spiritsNEWS October 2022

The Canadian Centre on Substance Use and Addiction (CCSA) published recently a proposal for revised Low-Risk Alcohol Drinking Guidelines (LRDGs) at no more than 2 drinks per week to reduce the risk of negative health consequences.

We are concerned about some of the fundamental methodological choices and approaches taken. The CCSA exclusively replies on a mathematical model which significantly limited the inclusion of available evidence and influenced the selection of studies. The lack of transparency as regards model codes and assumptions is another major issue as well as the way how the somewhat distorted model findings have been translated into public health messages which can be considered overly simplistic and alarmist.

The main objective of the LRDG is to help minimize long- and short-term alcohol-related harm, which is related to harmful drinking patterns (rather than alcohol consumption per se). People have the right to know and therefore LRDG’s role is to compile accurate, up-to-date information to consumers, which is a precondition for informed decision-making. Two fundamental issues need to be adequately addressed to achieve these objectives:

1. Robust trust in scientific evidence can only be established if researchers work according to the highest scientific standards, which includes not only comprehensiveness, but also transparency. The latter is important for study replicability, which applies especially to study designs, such as mathematical modelling, which CCSA opted for in its update of the LRDGs. Therefore, it would be fair and normal to expect the Technical Report to publicly reveal the model type, structure, concrete input factors, assumptions, and ideally model codes.
2. Scientific evidence needs to be translated into consumer-friendly information that is clear, easy to understand and as simple as possible. However, at the same time, oversimplification needs to be avoided as, otherwise, the information may become inaccurate and/or misleading.

Unfortunately, parts of the Public Summary can legitimately be seen to be overly simplistic, slogan-like, and inaccurate and hence bear the risk of misleading consumers. At the same time, the Technical Report is incomplete (due to selection bias), partially incorrect, lacks transparency and does not fulfil the fundamental scientific criteria of replicability (which could easily be amended since the revised LRDG are entirely based on mathematical modelling).

In sum, we do not see substantial changes in the available evidence-base to have happened to justify a drastic change in LRDGs. Furthermore, the Technical Report lacks transparency and does not fulfil the criteria of replicability. As a result, the model outputs seem to be overstated and unrealistic. In a next step, these findings were then translated into guidelines which can be considered alarmist, slogan-like and overly simplistic and which could confuse and mislead, rather than adequately inform, Canadian consumers.

We firmly believe that any decision to alter the current LRDGs must be based on a sound, robust, and comprehensive evaluation of the available scientific evidence at hand. In our view, the current LRDGs in Canada remain fully fit for purpose. There is no need for a revision of the guidelines if such a revision would risk to generate more harm (if not taken seriously by consumers) than benefit.