Relation between alcohol consumption in midlife and dementia in late lifeBMJ 2018; 362 doi: https://doi.org/10.1136/bmj.k3164 (Published 01 August 2018) Cite this as: BMJ 2018;362:k3164
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The public might be confused by the BMJ editorial on the relation between alcohol consumption and Alzheimer’s that was based on an observational study. Why? Because its salient message was that moderate alcohol consumption can ward of Alzheimer's. (1) The view that drinking has health benefits - even moderate drinking - has been criticized as a bias favoring the alcohol industry.
Health benefits related to moderate alcohol consumption have been touted for some time. Observational studies were central to this narrative. They underpinned the French Paradox - a low incidence of coronary artery disease attributed to drinking wine despite high levels of dietary cholesterol. The studies were a marketing coup for the alcohol industry. Red wine sales particularly increased after media coverage of the French Paradox. But the paradox was criticized as a hoax - an illusion emanating from biased studies that had commercial ties to industry and lacking strong evidence. (2) Others have been critical of studies on the protective cardio benefits of alcohol on methodological grounds. (3)
The alcohol industry is powerful and its influence can reach politicians, researchers, and government health agencies in some countries. A recently discredited National Institute of Health (NIH) study highlights the point. The trial was to measure how well the alleged health benefits of alcohol and moderate drinking hold up under greater scientific scrutiny. But an investigation resulted in the study being stopped due to embarrassing public revelations that NIH researchers were courting the alcohol industry behind the scenes to support the 100 million dollar trial. The “ trial design was such that it would not pick up harms, such as an increase in cancers or heart failure associated with alcohol, the investigation found.” (4) Industry has also paid journalists to try and influence public opinion on the health benefits of moderate alcohol consumption. (5) That alcohol has health benefits is an alluring narrative that is interwoven into our institutional and social fabric. And the narrative can be difficult to challenge. (6)
Against this backdrop the public might be muddled by the BMJ editorial citing the benefits of moderate drinking for Alzheimer’s. The editorial echoes the Lancet Commission on Dementia which recommended the benefits of moderate drinking. (7) The Commission was criticized for being biased in favor of industry - failing to note health risks associated with moderate alcohol consumption such as cancer. (8) The BMJ editorial did note that the issue is complicated and ideally a randomized trial is likely needed for a better scientific determination of the evidence. (1) Indeed, observation studies only suggest association and do not establish causation - a distinction the media can overlook when it comes to alcohol and other studies. (9) Now a just released global report on alcohol notes that no level of alcohol consumption is safe. (10)
Alain Braillon MD, PhD
Alcohol Treatment Unit
80054 Amiens CEDEX 1. France
Mark Wilson PhD
Canada, N1G 6S4
1.S.Yasar. Relation between alcohol consumption in midlife and dementia in late life. BMJ 2018; 362; k3164 doi: https://doi.org/10.1136/bmj.k3164
2. Alain Braillon. No Benefit to Die From Cancer With Healthy Coronary Arteries, Except in France. American Journal of Cardiology, Nov. 2012;
3. T. Stockwell, A. Greeer K. Filmore, T. Chikritzhs, C. Zeisser, How Good is the science?
4. Roni C. Rabin. Federal Agency Courted Alcohol Industry to Fund Study on Benefits of Moderate Drinking. New York Times, March 17, 2018.
5. Gary Schwitzer. Alcohol Industry isn’t just funding Studies; it’s also funding journalism to sway public opinion. Health News Review, June 6, 2017
6. Stephanie Mencimer, Did Drinking Give Me Breast Cancer? The science on the link is clear, but the alcohol industry has worked hard to downplay it; Mother Jones, May/June 2018
7. Gill Livingston, Andew Sommerland, Vasiliki Orteg.a et al. Orgeta V et al. Dementia prevention, intervention, and care.Lancet 2017; 390: 2673–2734
8. A. Braillon. Alcohol consumption and cognitive decline: the elephant in the room? Lancet Public Health.2018 May;3(5):e216. doi: 10.1016/S2468-2667(18)30070-7.
9. Michael Joyce. Drinking alcohol key to living past 90? What you need to know.
10. Robyn Burton, Nick Sheron. No level of alcohol consumption improves health. Lancet.
Competing interests: No competing interests
Alzheimer’s disease has increasingly plagued our ageing population, and the ongoing struggle to discover its pathogenesis or an effective treatment has been difficult. Recent research has shown that drinking moderate amounts of red wine lowers rates of dementia over a mean 23 year follow up period. (1) This interesting piece of research has led to much excitement, with newspapers claiming that experts say ‘drinking red wine every day can help prevent dementia.’ (2)
However, before we get too excited, we must be sure to think about the research a little more deeply. The research showed that red wine, and no other types of alcohol helped to prevent dementia. Other research over the past few years has elucidated the role of resveratrol in helping to prevent the progression of Alzheimer’s. This is a naturally derived molecule found in red wine, red grapes, raspberries and blueberries, which is a potent activator of SIRT1; it acts via this receptor to induce neuroprotection and longevity.(3)
Despite the fact that it is likely to be resveratrol rather than ethanol that is having the beneficial effect of preventing Alzheimer’s, most people tend to focus on the fun idea that drinking alcohol might actually be good for you. Whilst there is evidence for drinking red wine in moderation, surely consuming healthier alternatives that also contain resveratrol could be equally beneficial. Perhaps even better, as the encouragement of ‘moderate drinking’ is more likely to tip into ‘excessive drinking’ which then goes on to cause hippocampal atrophy and increase rates of Alzheimer’s.(1)
Whilst the research on the effects of alcohol consumption and progression of Alzheimer’s is exciting and useful, perhaps our focus should now be directed away from alcohol – looking into the effects of consuming more fruits containing resveratrol such as raspberries or red grapes to see if this has a similar effect to moderate consumption of red wine. If this was shown to be true it may be a more healthy way of teaching the public to help prevent Alzheimer’s, rather than encouraging alcohol consumption.
1. Yasar S. Relation between alcohol consumption in midlife and dementia in late life. BMJ [Internet]. British Medical Journal Publishing Group; 2018 Aug 1 [cited 2018 Aug 6];362:k3164. Available from: http://www.ncbi.nlm.nih.gov/pubmed/30068510
2. Drinking wine every day could help prevent Alzheimer’s, experts say | London Evening Standard [Internet]. [cited 2018 Aug 6]. Available from: https://www.standard.co.uk/news/health/drinking-wine-every-day-could-hel...
3. Sawda C, Moussa C, Turner RS. Resveratrol for Alzheimer’s disease. Ann N Y Acad Sci [Internet]. 2017 Sep [cited 2018 Aug 6];1403(1):142–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28815614
Competing interests: No competing interests