Critique #287 – Review of Evidence on Alcohol and Health

Authors

National Academies of Sciences, Engineering, and Medicine (NASEM)

Citation

The National Academies Press. Washington, DC. https://doi.org/10.17226/28582

Abstract

The abstract produced by NASEM is condensed from 14 pages down to the following main conclusions reached:

• Based on data from the eight eligible studies from 2019 to 2023, the Committee concludes that compared with never consuming alcohol, moderate alcohol consumption is associated with lower all-cause mortality (moderate certainty);
• The Committee determined that there was insufficient evidence to conclude the association between weight-related outcomes and moderate alcohol consumption compared with never consuming alcohol;
• The Committee concludes that compared with never consuming alcohol, consuming a moderate amount of alcohol was associated with a higher risk of breast cancer (moderate certainty). Also, no conclusion could be drawn regarding the association between moderate alcohol consumption compared with lifetime non-consumers and the risk of colorectal cancer. The Committee determined that no conclusion could be drawn regarding an association between moderate alcohol consumption and oral cavity, pharyngeal, oesophageal, or laryngeal cancers;
• The Committee concludes that compared with never consuming alcohol, consuming moderate amounts of alcohol is associated with a lower risk of CVD mortality in both females and males (moderate certainty);
• The Committee concludes there was insufficient evidence about the association between the risk of dementia, developing Alzheimer’s disease, or cognitive decline for those with no alcohol consumption compared to those with moderate alcohol consumption; and
• The Committee determined that no conclusion could be drawn regarding the association between maternal alcohol consumption during lactation and infant development.

Forum Summary

This important NASEM report is the official guidance for adults on alcohol consumption to help maintain health. The Committee reviewed the recent literature between 2010 and 2024 and considered previous guidelines focussing on eight specific questions, concerning overall mortality, cardiovascular diseases, cancers, neurocognitive health, overweight/obesity, lactation and infant development. The Report concentrated on the health outcomes related to moderate alcohol consumption only.

The Committee concludes that there is great consistency in their conclusion that moderate alcohol consumption, compared to never consuming alcohol, is associated with a lower risk of all-cause mortality and a decreased risk of myocardial infarction, nonfatal stroke and cardiovascular death.

Strong evidence of alcohol increasing the risk of cancer of the oral cavity, pharynx and oesophagus was based on higher alcohol intakes and therefore out of the scope of the NASEM report. Breast cancer in women is the only cancer type that is increased with moderate alcohol consumption. Risk increases may vary between 5 and 10 % increase per American standard drink (viz. 14 grams of alcohol) depending on the studies analysed. This peer-reviewed report acknowledges both the potential benefits and harms of moderate alcohol consumption. Although not stated as such by the Committee, there seems to be no reason to change the dietary guidelines for alcohol consumption based on the most recent scientific evidence.

Forum comments

Background to the NASEM report

The Dietary Guidelines for Americans (DGA), a joint publication of the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS), provide guidance to Americans to help them maintain health, achieve nutrient sufficiency, and help prevent diet-related chronic diseases through healthful dietary patterns. Included in the DGA recommendations is guidance for adults who consume beverages containing alcohol. This DGA guidance on alcohol is included because it is a source of energy for those who consume it and consider it part of their diet. Thus, it should be considered as a contributor to total caloric intake.

To that purpose, the National Academies of Sciences, Engineering, and Medicine (NASEM) (National Academies of Sciences, Engineering, 2025) convened a committee of experts (the Committee) to undertake a review of the recent scientific evidence (approximately between 2010 and 2024) on the relationship between consumption of alcohol and health outcomes. The Committee focused on eight specific questions, previously published by USDA and HHS concerning overall mortality, cardiovascular diseases, cancers, neurocognitive health, overweight/obesity, lactation and infant development. The report concentrated on the health outcomes related to moderate alcohol consumption only.

The Committee determined that the evidence for five health outcomes was sufficient to conduct a new systematic review. An important requirement was to have a comparison group that did not combine never-drinkers with former drinkers because of the resulting “abstainer bias” that would occur; therefore, results in this report are not directly comparable to past evidence that does include such abstainer bias.

Although individual studies used terminology variations such as light-to-moderate, the Committee adopted the term moderate, which it defined as consuming alcoholic beverages up to the limit defined by the Dietary Guidelines for Americans, i.e., two drinks or 28 grams of alcohol in a day for men and one drink or 14 grams of alcohol in a day for women.

Critique of the NASEM report

1. Methodology

This important exercise is the official guidance for adults on alcohol consumption to help maintain health. The report consisted of 254 pages, with extensive overviews of the research underlying their advice and transparently explaining and motivating the various steps taken.

The Committee concluded that little changes be made to the current guidelines based on the state-of-the-art most recent scientific literature. This means that consuming two drinks or 28 grams of alcohol in a day for men and one drink or 14 grams of alcohol in a day for women will maintain health, achieve nutrient sufficiency, and help prevent diet-related chronic diseases through healthful dietary patterns.

The Committee identified various limitations in the research conducted so far, an important aspect of epidemiological research into alcohol and health completely misused by a small group of scientists, is the abstainer bias. The Committee addressed the effect of bias caused by including former drinkers by excluding several otherwise relevant studies.

In addition, there are other limitations, such as a lack of standard definitions of alcohol consumption levels and a lack of standardized cutoffs for exposure categories, issues which the Committee urges scientists to address when publishing on alcohol consumption effects on human health.

The following comments address specific alcohol and health relationships.

All-cause mortality

The Committee mentions and subscribes that there is biological plausibility to the association between moderate alcohol consumption and a reduced risk for all-cause mortality. The Committee states that previous mechanistic studies have demonstrated that alcohol consumption influences serum levels of intermediary biological markers that are relevant to the incidence of heart disease and stroke (Brien et al., 2011). Specifically, the effects of alcohol consumption on lipids, platelet aggregation, inflammation, and endothelial function are well-documented in the literature (Hendriks, 2020). Furthermore, alcohol metabolites, including acetaldehyde, can play a role in the pathogenesis of certain cancers with downstream implications on the risk of death from cancers (Rumgay et al., 2021). The toxic effects of alcohol on several organs and the ability of alcohol to impair brain function have been well-established in the literature for trauma and deaths related to alcohol intoxication (Alpert et al., 2022). A combination of pathways is hypothesized to mediate the effects of alcohol consumption on multiple organ systems to ultimately affect all-cause mortality, including, for example, alcohol’s effect on altering haemostatic factors to increase the risk of bleeding. The investigation of the association of moderate alcohol consumption with all-cause mortality provides an integrated estimate of the full effect of this level of alcohol consumption (Colpani et al., 2018; Gmel et al., 2003).

In addition, the Committee considered the previous dietary guidelines to Americans given in reports issued in 2010, 2015 and 2020, concluding that there is great consistency in their conclusion that moderate alcohol consumption, compared to never consuming alcohol, is associated with a lower risk of all-cause mortality.

Cancer

The Committee’s conclusions on cancer and moderate alcohol consumption are interesting. The Committee indicates that although the mechanisms of carcinogenesis of alcohol and acetaldehyde for each cancer site have not been entirely determined, both human and animal studies provide evidence of their roles in carcinogenesis. The NASEM report focuses on what is known about the effects of moderate alcohol consumption on carcinogenesis and cancer as an outcome. Alcohol consumption and cancer incidence is topical since various U.S. and international agencies want to label alcoholic beverages as being carcinogenic. Of course, there are clear positive associations between mainly heavy alcohol consumption and some cancers, but no such association is found (yet) for other cancers. Moreover, inverse associations are described for lung (Fehringer et al., 2017), renal (Lee et al., 2007; Wozniak et al., 2015) and Hodgkin (Tramacere et al., 2012a) and non-Hodgkin lymphomas (Tramacere et al., 2012b).

Only a limited number of cancers were evaluated by the Committee since cancers of the oral cavity, pharynx, oesophagus, colorectum, and female breast were previously identified as causally related to alcoholic beverage consumption by the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) (WHO, 2014) and by the World Cancer Research Fund (WCRF) Continuous Update Project (World Cancer Research Fund / American Institute for Cancer Research, 2007). Exclusion of studies due to concerns about abstainer bias limited the number of studies that could be evaluated and, therefore, limited the overall conclusions regarding the effect of moderate alcohol consumption. Furthermore, strong evidence of alcohol increasing the risk of cancer of the oral cavity, pharynx and oesophagus was based on higher alcohol intakes and therefore out of the scope of the NASEM report.

Consequently, breast cancer in women is the only cancer type that is increased with moderate alcohol consumption. Risk increases may vary between 5 and 10 % increase per American standard drink (viz. 14 grams of alcohol) depending on the studies analysed.

For colorectal cancer, the Committee found that moderate alcohol consumption was associated with a statistically nonsignificant higher risk of colorectal cancer overall among males and females. It, therefore, resolved that no conclusion could be drawn regarding the association between moderate alcohol consumption compared with lifetime non-consumers and the risk of colorectal cancer. There were some concerns with the studies related to the risk of bias. Similarly, the Committee determined that no conclusion could be drawn on the association between moderate alcohol consumption and oral cavity, pharyngeal, oesophageal, or laryngeal cancers.

This means that for moderate alcohol consumers, the risk for cancers is limited to breast cancer in women and may be relevant to colorectal cancer in both men and women. The risk for other cancers caused by alcohol consumption is probably limited to those who drink more than the current US guidelines.

Cardiovascular disease

Conclusions on cardiovascular diseases, specifically myocardial infarction, stroke, and cardiovascular death, are in line with previous DGAs and have an extensively researched biological plausibility. The NASEM conclusions are in line with previous ISFAR critiques, namely moderate alcohol consumers have a decreased risk of myocardial infarction, nonfatal stroke and cardiovascular death. Thus, with moderate certainty, moderate alcohol consumption is associated with cardioprotection, and a lower cardiovascular mortality.

Cognitive decline and dementia

An extensive review of the risk related to moderate alcohol consumption and cognitive decline and dementias did not lead to new conclusions of the Committee due to insufficient evidence. This a difficult area to study and needs innovative research before any conclusion can be drawn.

The Committee indicated that awareness of ‘abstainer bias’ is growing, as per the number of eligible studies that could be analysed. This is a positive development because the issue of abstainer bias is especially critical for moderate alcohol consumers. Heavy drinking and alcohol abuse are unhealthy behaviours and need hardly any further scientific substantiation. Drinking moderately, however, needs further substantiation as a healthy lifestyle factor with biological plausibility contributing to a part of daily life and in many social scenarios. These scenarios include celebrations and social interactions pursuing entertainment and enjoyment as drinking alcoholic beverages is for many. This is also a benefit of moderate alcohol consumption, recognised by the Committee as social connectivity.

Therefore, this peer-reviewed report instigated by NASEM acknowledges both the potential benefits and harms of moderate alcohol consumption. The Committee, however, calls for higher quality studies such as double-blind randomised controlled trials to reduce bias and confounding, to enable even more definitive conclusions (Mukamal et al. 2016.)

 Specific Comments from Forum Members

Forum Member Teissedre comments: “This major report on the health effects of alcohol should inform dietary guidelines for 2025 Americans, finding that moderate drinkers had lower all-cause mortality and a lower risk of death from cardiovascular disease than those who never drink or are abstinent The National Academies of Sciences, Engineering, and Medicine (NASEM) Evidence Review summarizes the available evidence published over the years. last five to fifteen years on the link between moderate alcohol consumption and lactation, weight, cancer, cardiovascular disease, neurocognition and all-cause mortality. Moderate drinking is defined as two drinks per day for men and one drink per day for women Because the Committee’s findings are based on associations, the report does not explain whether alcohol consumption is directly responsible for the results.

The current Dietary Guidelines for Americans recommend that men limit their alcohol consumption to 2 drinks or less per day and for women one drink or less per day. This recommendation is supported by the preponderance of evidence. Additionally, the current Dietary Guidelines for Americans recognize that excessive alcohol consumption should be avoided and describe how calories from alcoholic beverages should be accounted for, as they can easily contribute to excessive caloric intake.

It must be emphasized for the future that the type of alcoholic beverage (wine, beer, spirits) consumed, as well as the context, habits (cultural, food/lifestyle, physical activity), must be taken into account for the definition of frequencies appropriate consumption. Research appears necessary in particular on the consumption of wine in the context of a diet and a healthy lifestyle, given that wine also contains beneficial constituents (phenolic antioxidants).”

Forum Member Skovenborg muses on the issue of underreporting, saying: “The authors of many studies are aware of the fact that self-reports may underestimate alcohol consumption, often by an average of one-half, and note that the actual levels of intake beneficial to health may actually be twice as high as those observed, however, this is most often not reflected in their conclusions about average beneficial levels of alcohol consumption.”

Forum Member Ellison stated: “The Committee that was created to review reports regarding the relation of alcohol consumption to health outcomes focused only on papers published since 2010.  Thus, they often had insufficient data to be able to reach conclusions for many associations.  Further, they used data only on total alcohol consumption, with inadequate information on the type of beverage or the pattern of drinking (such as frequency of consumption, drinking with or without food, etc.).  Further, they did not have the opportunity to include in their reviews data from a very large number of prior well-done, unbiased studies, including many that not only limited the comparison group to lifetime abstainers but also adequately controlled for other potentially confounding variables. 

Despite these limitations, the conclusions from this Committee strongly support results from a very large number of earlier studies that clearly showed both risk and benefits from alcohol consumption, and particularly that moderate drinkers have a lower risk than abstainers for cardiovascular disease (CVD) and total mortality.  The more recent studies reviewed by the Committee show a remarkable consistency with results from earlier research (and consistency is a very important component when trying to determine if an association can be assumed to be causal). 

That moderate drinking may protect against CVD and mortality have been found in almost all well-done studies despite large variations in the populations studied in terms of age, gender, ethnicity, and culture, and within diverse populations with different lifestyles.  Further, the associations have had to be related to disease outcomes despite recognized imprecise estimates of alcohol consumption, based almost exclusively on self-reports of drinking habits.  It reminds me of the long-recognized and accepted increased risk of CVD found for hypertension despite very imprecise assessments of blood pressure; for many studies, they are based on the measurements in physicians’ offices that are often quite different from the long-term level of blood pressure.  With more precise and stable measurements of usual blood pressure, it would be expected that hypertension would be an even stronger risk factor for CVD.  With more accurate assessment methods for alcohol consumption, should we not expect even a stronger relation between moderate drinking to disease outcomes?

In any case, this Committee report presents results from recent epidemiologic studies that indicate that, for many adults, moderate drinking should not be considered unhealthy.  This review does not support the contention of some individuals, that complete abstinence for everyone should be the message to the public.  In addition, we now have an immense number of basic scientific experiments and clinical trials that have identified numerous mechanisms by which alcoholic beverages could have a protective effect on atherosclerosis and thrombosis.  Maybe it is time to focus research on providing further insight into the mechanisms that may help explain the observed protective effects of low-to-moderate alcohol consumption and suggest further potential measures for prevention and treatment of CVD.” 

Forum Member Harding considers that “this review represents a huge amount of work, and its sheer size makes it a real challenge to see the wood for the trees.  That said, the following points occur to me:

1.  It was good to see the Committee focussing on the effects of moderate consumption (page 2).

2.  The eight questions this review addresses are clearly stated in Box 1-3 (page 23).  I don’t see the point of including No. 5 (all-cause mortality).  This is simply the net result in a population of the effect of alcohol on specific diseases.  No one dies of all-cause mortality.

3.  The review focussed mainly on epidemiological studies and reviews but I was pleased to see the ‘biological plausibility’ feature in each of the sections that addressed each of the eight questions.  However, the balance given to each is not clear, and it is significant that the words, ‘biological plausibility’ don’t feature at all in Chapter 2, ‘Approach to the Task’.  In all of its 228 pages, the word ‘association’ appears 285 times. Most of the findings at the end of each Chapter are based on the outcome of epidemiological studies and reviews and often feature the words ‘association’ and ‘risk’, but rarely, if ever, mention mechanisms of action.

4.  This is my main problem with the review as a whole.  The purpose of epidemiology is to identify associations, to indicate the areas where future research should examine, and to try to work out what is going on.  Having done that, epidemiology needs to get out of the way.  No amount of epidemiology can answer the question, ‘is the association causal?’

5.  The sections on Biological Plausibility begin to do that but are nowhere near enough in-depth.  Where, for example, is a thorough analysis of the effect of alcohol consumption on insulin sensitivity and insulin levels, now recognised as significant in the development of a range of chronic diseases, or on other biomarkers?  It is the outcome of these studies on which reviews like this one should base their conclusions, on the actual effect of alcohol consumption on metabolism, rather than on increasingly sophisticated analysis of epidemiological data.  In the Chapter ‘Future Directions’, the authors call for randomised control trials to provide the evidence they need (page 187) and then explain why these are not possible.  The lack of randomised control trials has not proved a barrier to sensible public health advice in other areas, for example, on smoking and lung cancer.

6. The Bradford-Hill criteria for causation should be applied to the body of evidence summarised in each of the eight questions, and this analysis should inform the conclusions.”

Forum Member Parente reiterates that “there seems to be no reason to change the dietary guidelines for Americans on alcohol consumption based on the most recent scientific evidence”.

Forum Member de Gaetano provides the following observations:

“1.   Under-reporting: the beneficial effects of alcohol on CVD might occur even at doses higher than that shown on a J curve, while the detrimental effects on cancer attributed to low alcohol doses shown, might be, in fact, linked to higher doses. Underreporting differently affects benefits or risks;

2.    The limitations of observational studies that render doubtful the beneficial effects of alcohol on CVD, equally apply to the detrimental effects on cancer. One accepts both or none; and

3.    A brief methodological comment might be made from the recent paper by Domínguez-López et al. (2025) that using urinary tartaric acid as a measure of wine consumption, confirmed the beneficial effects of wine as previously observed using alcohol self-reported data.

A final bitter joke: drinking hydrogen peroxide in low doses is beneficial but at high doses is lethal.”

References

Alpert, H. R., Slater, M. E., Yoon, Y.-H., Chen, C. M., Winstanley, N., & Esser, M. B. (2022). Alcohol consumption and 15 causes of fatal injuries: A systematic review and meta-analysis. Am J Prevent Med, 63(2), 286–300. https://doirorg/10.1016/j.amepre.2022.03.025

Brien, S. E., Ronksley, P. E., Turner, B. J., Mukamal, K. J., & Ghali, W. A. (2011). Effect of alcohol consumption on biological markers associated with risk of coronary heart disease: systematic review and meta-analysis of interventional studies. BMJ, 342, d636. https://doi.org/10.1136/bmj.d636

Colpani, V., Baena, C. P., Jaspers, L., van Dijk, G. M., Farajzadegan, Z., Dhana, K., Tielemans, M. J., et al. (2018). Lifestyle factors, cardiovascular disease and all-cause mortality in middle-aged and elderly women: a systematic review and meta-analysis. Eur J Epidemiol, 33(9), 831–845. https://doi.org/10.1007/s10654-018-0374-z

Fehringer, G., Brenner, D. R., Zhang, Z. F., Lee, Y. A., Matsuo, K., Ito, H., Lan, Q., et al. (2017). Alcohol and lung cancer risk among never smokers: A pooled analysis from the international lung cancer consortium and the SYNERGY study. Int J Cancer. https://doi.org/10.1002/ijc.30618

Gmel, G., Gutjahr, E., & Rehm, J. (2003). How stable is the risk curve between alcohol and all-cause mortality and what factors influence the shape? A precision-weighted hierarchical meta-analysis. Eur J Epidemiol, 18(7), 631–642. https://doi.org/10.1023/a:1024805021504

Hendriks, H.F.J. (2020). Alcohol and Human Health: What Is the Evidence? Ann Rev Food Sci Technol, 11(1), 1–21. https://doi.org/10.1146/annurev-food-032519-051827

Lee, J. E., Hunter, D. J., Spiegelman, D., Adami, H. O., Albanes, D., Bernstein, L., van den Brandt, P. A., et al. (2007). Alcohol intake and renal cell cancer in a pooled analysis of 12 prospective studies. J Natl Cancer Inst, 99(10), 801–810. https://doi.org/10.1093/jnci/djk181

Mukamal, K.J., Clowry, C.M., Murray, M.M., Hendriks, H.F., Rimm, E.B., Sink, K.M., Adebamowo, C.A., et al. (2016) Moderate alcohol consumption and chronic disease: The case for a long-term trial. Alcohol Clin Exp Res, 40(11), 2283-2291. https://doi.org/10.1111/acer.13231.

National Academies of Sciences, Engineering, and M. (NASEM). (2025). Review of Evidence on Alcohol and Health. The National Academies Press. Washington, DC., 1–254.

Rumgay, H., Murphy, N., Ferrari, P., & Soerjomataram, I. (2021). Alcohol and Cancer: Epidemiology and Biological Mechanisms. Nutrients, 13(9). https://doi.org/10.3390/nu13093173

Tramacere, I., Pelucchi, C., Bonifazi, M., Bagnardi, V., Rota, M., Bellocco, R., Scotti, L., et al. (2012a). A meta-analysis on alcohol drinking and the risk of Hodgkin lymphoma. Eur J Cancer Prev, 21(3), 268–273. https://doi.org/10.1097/CEJ.0b013e328350b11b

Tramacere, I., Pelucchi, C., Bonifazi, M., Bagnardi, V., Rota, M., Bellocco, R., Scotti, L., et al. (2012b). Alcohol drinking and non-Hodgkin lymphoma risk: a systematic review and a meta-analysis. Ann Oncol, 23(11), 2791–2798. https://doi.org/10.1093/annonc/mds013

WHO. (2014). Global status report on alcohol and health.

World Cancer Research Fund / American Institute for Cancer Research. (2007). Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. AICR, Washington DC.

Wozniak, M. B., Brennan, P., Brenner, D. R., Overvad, K., Olsen, A., Tjonneland, A., et al. (2015). Alcohol consumption and the risk of renal cancers in the European prospective investigation into cancer and nutrition (EPIC). Int J Cancer, 137(8), 1953–1966. https://doi.org/10.1002/ijc.29559

The following International Scientific Forum on Alcohol Research members provided comments on, and supported this critique:

Henk Hendriks, PhD, Zeist, Netherlands

Creina Stockley, PhD, MBA, Independent consultant and Adjunct Senior Lecturer in the School of Agriculture, Food and Wine at the University of Adelaide, Australia

Pierre-Louis Teissedre, PhD, Faculty of Oenology–ISVV, University Victor Segalen Bordeaux 2, Bordeaux, France

R. Curtis Ellison, MD, Section of Preventive Medicine/Epidemiology, Boston University School of Medicine, Boston, MA, USA

Erik Skovenborg, MD, Formerly Family Medicine specialist, member of the Scandinavian Medical Alcohol Board, Aarhus, Denmark

Richard Harding, PhD, Formerly Head of Consumer Choice, Food Standards and Special Projects Division, Food Standards Agency, London, UK

Tedd Goldfinger, DO, FACC, Desert Cardiology of Tucson Heart Center, University of Arizona School of Medicine, Tucson, AZ, USA

Monika Christmann, PhD, Head of Institute, Department of Enology and Professorship for Enology, Hochschule Geisenheim University, Germany

Andrew L. Waterhouse, PhD, Professor Emeritus of Enology, Department of Viticulture and Enology, University of California, Davis, CA, USA

Fulvio Ursini MD, Emeritus Professor of Biochemistry, University of Padova, Padova, Italy

Ramon Estruch, Ramon Estruch, MD, PhD.  Associate Professor of Medicine, University of Barcelona, Spain

Matilde Parente, MD, Consultant in Molecular Pathology/Genetics and Emerging Technologies, San Diego, CA, USA

Fulvio Mattivi, MSc, Professor and Scientific Advisor, Research and Innovation Centre, Fondazione Edmund Mach, in San Michele all’Adige, Italy

Giovanni de Gaetano, MD, PhD, Department of Epidemiology and Prevention, IRCCS Istituto Neurologico Mediterraneo NEUROMED, Pozzilli, Italy

Lynda H. Powell, MEd, PhD, Chair, Dept of Preventive Medicine, Rush University Medical School, Chicago, IL, USA

Luc Djoussé, MD, DSc, Dept. of Medicine, Division of Aging, Brigham & Women’s Hospital and Harvard Medical School, Boston, MA, USA

Linda McEvoy, PhD, Department of Radiology, University of California at San Diego (UCSD), La Jolla, CA, USA

Mladen Boban, MD, PhD, Professor and Head of the Department of Pharmacology, University of Split School of Medicine, Croatia

Dominique Lanzmann-Petithory,MD, PhD, Nutrition/Cardiology, Praticien Hospitalier Hôpital Emile Roux, Paris, France