Scientists initially believed moderate alcohol consumption could be beneficial due to studies showing a J-curve relationship, where moderate drinkers had a lower risk of death compared to abstainers. This was supported by theories like the Mediterranean diet and the French paradox, which suggested red wine could reduce heart disease risks.
The studies were flawed because they compared moderate drinkers to abstainers who had already quit drinking due to health issues. This created a bias, making moderate drinkers appear healthier when they were simply a healthier group to begin with, not because of alcohol consumption.
The mortality risk of one alcoholic drink is equivalent to that of one cigarette. This risk increases with higher alcohol consumption, where two to four drinks a day can equate to 10 to 15 cigarettes a day in terms of mortality risk.
One drink a day is estimated to reduce life expectancy by an average of three months for the general population, according to Canadian guideline estimates.
The belief has persisted because alcohol is a widely enjoyed recreational drug, and the idea of its benefits is appealing. Additionally, mixed messages and divided opinions in public discourse have contributed to its continued acceptance.
Public opinion has shifted significantly, with a decline in the belief that moderate alcohol consumption is beneficial. While 40% of people once believed it was good for you, that number has dropped to about 10%, and more people are now aware of the small health risks associated with low-volume drinking.
Tim Stockwell suggests that governments should publicly acknowledge the risks of alcohol and implement health warning labels on alcohol containers to inform consumers about its carcinogenic effects and other health risks.
For the regular drinker, the studies that say a daily tipple is better for a longer life than avoiding alcohol completely are a source of great comfort. But a new analysis challenges that thinking and says it was based on flawed research that compares drinkers with people who are sick and sober. In this episode from August, Madeleine Finlay hears from the study’s lead author, Tim Stockwell, a scientist at the Canadian Institute for Substance Use Research at the University of Victoria, to find out why scientists (including him) were so convinced, and what the actual risks of alcohol are. Help support our independent journalism at theguardian.com/sciencepod)