Moderate Drinking Brings No Health Benefits, Contrary to Prior Research

Previous studies demonstrating the health benefits of moderate alcohol drinking were of low quality, according to a new analysis.

In many cases, these inferior studies would label older participants who had given up alcohol due to ill health as drinkers “who consumed less than weekly”.

By comparing such “drinkers” to younger, healthier people who drank more regularly, many of these prior studies came to the erroneous conclusion that moderate drinking has its health perks.

After discounting these poorer studies and focusing only on thorough research in their review, the researchers from the Canadian Institute for Substance Use Research (CISUR) found no evidence that light-to-moderate drinkers lived longer.

The findings were published in the Journal of Studies on Alcohol and Drugs.

Research responsibly

While red wine is known for its purported health boons, decades-old research has suggested that any alcoholic beverage, when drunk in moderation, can offer a similar kind of benefit.

One study published in 1997, for instance, found that men and women who drank one or two drinks per day had 30-40% lower total cardiovascular disease mortality than non-drinkers.

To probe these kinds of findings, a research group from CISUR and the Canadian Centre on Substance Use and Addiction reevaluated 107 longitudinal alcohol-health studies, which accounted for 4,838,825 participants and 425,564 deaths.

The researchers divided the studies into either “lower” or “higher” quality categories based on whether the comparison group of teetotalers/irregular drinkers included participants with ill health.

After doing so, they found that estimates for all-cause mortality risk for low-volume drinkers were significantly higher in the studies that: used younger cohorts, excluded potential participants with current or prior ill health, assessed alcohol use over less than 30 days, didn’t suffer from “abstainer bias” in the reference group and didn’t control for smoking status.

The researchers concluded that participant selection biases had warped the findings of dozens of alcohol mortality studies over the years, creating “the false appearance of health benefits from moderate drinking.”

“If you look at the weakest studies,” said Tim Stockwell, former director of the CISUR,  “that’s where you see health benefits.”

The health toll of alcohol

Beyond these outdated studies, modern alcohol research has illuminated many of the substance’s health risks, such as the risk of developing bowel and female breast cancer – risks that increase substantially the more alcohol is consumed.

Indeed, according to the World Health Organization (WHO), this risk and the other negative effects of alcohol (increased chance of developing type 2 diabetes) outweigh any health benefits the beverage could offer.

“There are no studies that would demonstrate that the potential beneficial effects of light and moderate drinking on cardiovascular diseases and type 2 diabetes outweigh the cancer risk associated with these same levels of alcohol consumption for individual consumers,” the WHO stated in 2023.

Dr. Stockwell concurs. “There is simply no completely ‘safe’ level of drinking,” he said.

Reference: Stockwell T, Zhao J, Clay J, et al. Why do only some cohort studies find health benefits from low volume alcohol use? A systematic review and meta-analysis of study characteristics that may bias mortality risk estimates. Journ of stud on alco and dru. 2024. doi: 10.15288/jsad.23-00283