Some surprising benefits have emerged from a new federal review of scientific evidence on the relationship between moderate alcohol consumption and health outcomes.
Released by the National Academies of Sciences, Engineering and Medicine last month, and sponsored by the Department of Agriculture, the report is intended to guide the development of the next edition of the Dietary Guidelines for Americans. However, it stops short of offering specific dietary recommendations.
While some findings suggest potential benefits, experts urge caution when interpreting the results, emphasizing the need for a balanced understanding of both the risks and rewards.
The report concludes that moderate drinkers, compared to nondrinkers, had a lower risk of nonfatal myocardial infarction — heart attack — and nonfatal stroke, though the certainty of these findings is low. It also found a lower risk of cardiovascular mortality in both men and women, with moderate certainty.
Moderate alcohol intake, as defined by the study, is two drinks in a day for men and one drink a day for women, as recommended in the current Dietary Guidelines for Americans, published in 2020. The report does not compare health outcomes across different types of alcohol.
The report also states, with moderate certainty, that moderate alcohol consumption is associated with lower all-cause mortality compared to never consuming alcohol. All-cause mortality encompasses the total number of deaths in a population from any cause, suggesting that moderate drinkers may experience certain health advantages over lifetime abstainers. However, experts caution that these findings are observational and influenced by numerous factors, such as underlying health conditions, lifestyle and socioeconomic status, which may confound the relationship between alcohol consumption and longevity.
“If the findings are summarized as ‘moderate alcohol consumption is good for you or can prolong your life,’ or if this message overshadows and gets more attention than the inconclusive or less-positive findings, then the public will not be given the opportunity to acknowledge that risks along with the pros,” said James Mahoney, an associate professor and clinical neuropsychologist in the behavioral medicine and psychiatry department of West Virginia University’s Rockefeller Neuroscience Institute.
“The evidence base from which to draw conclusions about alcohol and health is imperfect, and conducting the research has many challenges — such as a lack of standardization for terms like ‘non-drinker’ or ‘moderate drinker’ and the possibility that people are underreporting their own alcohol consumption,” said Ned Calonge, chair of the Committee on the Review of Evidence on Alcohol and Health, in a press release from mid-December. Calonge is also associate dean for public health practice and professor of epidemiology at Colorado School of Public Health and a professor of family medicine at the University of Colorado School of Medicine.
“Our report outlines what evidence is available on alcohol and health to inform the next Dietary Guidelines for Americans, and highlights research gaps that, if addressed, could strengthen the information available to us,” Calonge said.
While Mahoney, who was not involved in the study, said he doubts the report will directly encourage overconsumption, he warned of potential unintended consequences if the risks are overshadowed by the surprising benefits. This depends, he said, on how the report is relayed to the public.
“I do believe that unintended negative consequences are certainly reasonable … if individuals don't acknowledge that moderate alcohol use can progress to heavier alcohol use and eventually lead to development of an alcohol use disorder,” he said in an email.
“The report was thorough and comprehensive and did emphasize the gaps and limitations accordingly, emphasizing the need for more rigorous research,” he said. “The hope is that given the comprehensive nature of the report and acknowledgement of the limitations and lack of conclusive evidence across many domains will also be considered when shaping the [2025 Dietary] Guidelines.”
Examining five main health risks, report conclusions include:
- All-cause mortality — With moderate certainty, moderate alcohol consumption is associated with a reduced risk of all-cause mortality, which refers to the total number of deaths in a population from any cause.
- Weight changes — No definitive conclusions could be drawn between moderate alcohol intake and weight-related outcomes, such as changes in weight and body mass index (BMI) or the risk of obesity, when compared to nondrinkers. The report concluded with low certainty that in men, changes in BMI, risk of being overweight and risk of obesity are similar among men who consume a moderate amount of alcohol. The evidence for changes in BMI and the risk of being overweight and obesity among women are inconsistent.
- Cancer — With moderate certainty, moderate alcohol consumption is associated with a higher risk of female breast cancer compared to never consuming alcohol. With low certainty, the report also found that higher levels of moderate alcohol consumption are associated with a greater risk of breast cancer compared to lower levels. The report concluded with low certainty that higher levels of moderate alcohol consumption may be associated with an increased risk of colorectal cancer compared to lower levels. The report could not draw any conclusions about moderate alcohol consumption and the risk of these cancers.
- Cardiovascular disease — Compared to non-drinkers, moderate alcohol consumption is associated with a lower risk of nonfatal heart attacks and strokes, both with low certainty. It also found a lower risk of cardiovascular mortality in men and women, with moderate certainty.
- Neurocognition — No conclusions could be drawn about the relationship between moderate alcohol consumption and the risk of Alzheimer’s disease, dementia or cognitive decline when compared to nondrinkers, occasional drinkers or heavy drinkers.
Mahoney acknowledged that risks like cancer, liver disease and effects on mental health, among others, require further investigation.
“The report does not show that there was evidence of a relationship between moderate drinking and increased risks of certain types of cancer. The impact of moderate drinking on other physical complications such as liver disease warrants further investigation, especially in light of moderate drinking progressing to an alcohol use disorder. And certainly the mental health comorbidities need to be considered” especially when moderate alcohol consumption is used as a coping mechanism for dealing with depression or anxiety.
“Then the possibility that moderate drinking may increase and progress to more problematic levels over time as a way of coping in times of increased emotional symptoms is certainly plausible,” he said.
Despite these concerns, Mahoney said that the report provides valuable insights into the potential benefits of moderate alcohol consumption while emphasizing its limitations. He believes the findings should serve as a starting point for deeper inquiry rather than definitive conclusions.
“The finding that there was moderate certainty that moderate alcohol consumption is associated with lower all-cause mortality is significant, though I believe the most significant aspect of the report is that it highlights how much research needs to be done in order to make more conclusive determination of the impact of moderate alcohol use and highlights the gaps in the literature,” Mahoney said.
First Published: January 5, 2025, 10:30 a.m.
