Scientific evidence on the health benefits of alcohol suddenly began to fade: “It’s complicated”

Lifelong abstainers have the lowest risk of death

Scientific evidence on the health benefits of alcohol is fading. A new study has exposed the shortcomings of older, often industry-funded studies, and found that lifelong abstainers have the lowest risk of death.

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People have been used to the idea that alcohol can be good for their health for almost as long as they have been drinking it, The Guardian reports. In ancient China, rice wine was widely used for medicinal purposes, while Hippocrates, the ancient Greek «Father of Medicine», advocated moderate drinking for the mind, body and soul.

Later, temperance advocates who urged 19th-century workers to give up drinking were met with resistance from those who believed beer was essential for good health.

Surprisingly, this theory has since gained widespread support from modern science. When studying how the amount of alcohol you drink relates to your risk of heart disease and death, researchers have found a puzzling but consistent “J-shaped curve,” suggesting that drinking a little alcohol is healthier than abstaining altogether.

But the idea has been controversial from the start, and as research methods become more sophisticated, a different picture is emerging that ordinary drinkers may not be happy to hear, The Guardian notes.

The first evidence of alcohol's beneficial effects came from a small 1974 study of 474 people that found that people who drank light amounts of alcohol had a lower risk of heart attack than both heavy drinkers and abstainers. Over the next few decades, as scientists were able to survey more people, collect more data, and take into account more factors, studies repeatedly reached the same conclusion.

More recently, in 2011, a meta-analysis published in the journal BMJ concluded that the lowest risk of coronary heart disease could be achieved by drinking 1-2 drinks per day. And two years ago, a large-scale study «Global Burden of Disease» showed that alcohol may be beneficial for people over 40, contradicting their own 2018 finding that any amount of drinking is harmful.

However, throughout these studies, scientists have consistently pointed out serious methodological flaws. One of the main problems is that the risk of death among the non-drinking group is often overestimated due to the significant number of «alcoholics». – people who quit drinking for health reasons. In comparison, it seems clear that sensible people who drink in moderation are more likely to live longer.

Another problem is that many studies ask participants to self-report their alcohol consumption, and their answers are likely to be inaccurate and may change over time. When researchers take these factors into account, the J-shaped curve turns into a simple straight line. A paper published earlier this week reanalyzed data from previous studies and found that those who never drank alcohol had the lowest risk of death.

But according to Tim Stockwell, lead author of the latest study, this shouldn't be taken as a definitive answer; rather, it's an indication of how much work remains to be done. «Ultimately, we don't take our findings literally, we don't think this is necessarily an accurate picture,» he said. «It's more like a sign of how bad the research is.»The main reason it has proved so difficult to sort out these factors is that alcohol affects everyone differently, and everyone drinks for different reasons. «Alcohol is complicated because it has so many different biological effects,» says Iona Millwood, a researcher at the University of Oxford. «People's drinking patterns are also determined by many other characteristics that themselves have an impact on health.»To avoid these problems, Millwood's study used a new approach that separated people into those genetically predisposed to drinking more or less alcohol, rather than relying on self-reported levels. They found that for 61 different outcomes, including many cancers, liver disease, stroke and overall mortality, the message was simple: the more you drink, the higher your risk. Other genetic analyses have found similar results.

It’s important to note that the supposed benefits of alcohol apply only to cardiovascular disease and overall mortality (though Stockwell suspects that the former drives the latter). For many other diseases, the evidence is much clearer. For example, the vast majority of people agree that any amount of alcohol increases the risk of cancer, as supported by a large analysis comparing light drinkers with lifelong abstainers, which found significantly lower rates of mouth, bowel and breast cancer in non-drinkers.

So, if mounting evidence denies the beneficial effects of alcohol, why is this idea so firmly ingrained in the public consciousness? Mark Petticrew, a researcher at the London School of Hygiene and Tropical Medicine, said he believes the drinks industry's efforts explain a lot. “One of the reasons the public believes in these protective effects is because the industry funds and promotes research, as the tobacco industry did.

As evidence, Petticrew cites an analysis conducted in 2021, which analyzed 60 different reviews of the effects of alcohol on the risk of cardiovascular disease. It found that 14 of them were either directly funded by the alcohol industry or recruited by researchers with links to the alcohol industry. All 14 scientists concluded that drinking small amounts of alcohol may protect against cardiovascular disease.

Ultimately, as much as people and beverage companies might like to believe, drinking alcohol every day is the key to long life, scientific support for this idea appears to be fading, The Guardian concludes.