What Is Considered ‘Moderate Drinking’?

Over the past several years, there has been a rise in alcohol-related deaths and a steady wave of news about the health risks of drinking. Calls for people to drink only in moderation have become more urgent. But what, exactly, does that mean?

“Tongue in cheek, people have defined it as not drinking more than your doctor,” said Tim Stockwell, a scientist at the Canadian Institute for Substance Use Research.

More officially, in the United States, moderate drinking is defined as one drink or less per day for women and two drinks or less per day for men. But other countries define moderate drinking, also called low-risk drinking, differently, and recent research around alcohol’s health harms has raised questions about current guidelines.

How are the guidelines set?

Experts used to think that low or moderate amounts of alcohol were good for you. That assumption was based on research showing that people who drank in moderation lived longer than those who abstained or drank excessively. The longevity benefit disappeared around two drinks a day for women and three drinks a day for men, Dr. Stockwell said.

But many researchers now think that those conclusions were based on data analyses that had “all kinds of methodological problems,” said Elizabeth Mayer-Davis, a professor of nutrition and medicine at the University of North Carolina, Chapel Hill.

For example, one issue was that many people who abstained from alcohol did so because they had existing health problems, while people who drank moderately were more likely to have healthy lifestyle habits. It created “really what was an illusion of health benefits with low to moderate amounts of drinking,” Dr. Mayer-Davis said.