The benefits and risks of alcohol consumption have been controversial for decades. Some studies have suggested that “moderate” amounts of alcohol have health benefits. In other words, people who drink a little alcohol for longer life might be doing themselves some good. Other experts maintain that even moderate alcohol consumption will shorten your life. Confusing? You bet! And it has only become more confounding recently. Headlines proclaim that no amount of alcohol consumption is good for you–or that drinking won’t kill you. Let’s take a look at the evidence.
Why We Can’t Count on Alcohol for Longer Life:
A systematic review of 107 trials triggered the latest rash of headlines on whether alcohol affects mortality (JAMA Network Open, March 31, 2023). This ambitious study covered 4.8 million people who had told scientists whether and how much they drank. To determine whether people who drink just a little on a regular basis have any health advantage, the researchers compared them to individuals defined as occasional drinkers, less than one drink a week.
As expected, this study confirmed previous research showing that habitual heavy drinkers are more likely to die prematurely. (This kicks in at lower levels of drinking for women than for men.) But what about the light-to-moderate drinkers? The analysis shows no reduction in premature mortality for people taking two drinks or less a day. On the other hand, at that level of alcohol consumption, people were also no more likely to die ahead of their time.
The scientists concluded:
“In this updated systematic review and meta-analysis, daily low or moderate alcohol intake was not significantly associated with all-cause mortality risk, while increased risk was evident at higher consumption levels, starting at lower levels for women than men.”
Needless to say, these investigators and most commentators warn people against drinking alcohol for the purpose of improving their health.
Previous Studies on Alcohol and Mortality:
To really understand the controversy, we should review an earlier study showing that drinking a little helped people with heart disease (BMC Medicine, July 27, 2021). Moreover, previous research spelled out how much alcohol is enough to be beneficial and how much is harmful (PLoS Medicine, June 19, 2018). The results might surprise you. First, though, the opposing perspectives.
Alcohol for Longer Life Proponents:
The Mayo Clinic reports on its website that moderate alcohol consumption can:
- “Reduce your risk of developing and dying from heart disease
- “Possibly reduce your risk of ischemic stroke (when the arteries to your brain become narrowed or blocked, causing severely reduced blood flow)
- “Possibly reduce your risk of diabetes”
The experts for the Mayo Clinic define “moderate” alcohol consumption as:
- One drink a day for women.
- Two drinks a day for men under 65 and one drink for older men
- A drink equals a 5-ounce glass of wine or a 12-ounce glass of beer. A drink of liquor equals 1.5 ounces.
Alcohol for Longer Life Opponents:
A systematic review and meta-analysis published in the Journal of Studies on Alcohol and Drugs (online, March 22, 2016) reports:
“Estimates of mortality risk from alcohol are significantly altered by study design and characteristics. Meta-analyses adjusting for these factors find that low-volume alcohol consumption has no net mortality benefit compared with lifetime abstention or occasional drinking. These findings have implications for public policy, the formulation of low-risk drinking guidelines, and future research on alcohol and health.”
Alcohol and Dementia?
The data regarding alcohol consumption and Alzheimer’s disease are, unfortunately, even more confusing. Some research suggests that alcohol consumption is bad for the brain.
Norwegian investigators reported (European Journal of Epidemiology, online, May 13, 2015):
“The present study finds that frequent alcohol consumption is associated with a higher dementia risk compared to infrequent alcohol consumption. The same pattern of associations is indicated for Alzheimer’s disease and for vascular dementia, but the latter results were not statistically significant.”
Other research suggests that moderate alcohol consumption may reduce the risk for dementia: (Neuropsychiatric Disease and Treatment, online, Aug. 11, 2011)
“We reviewed 143 papers that described the relationship between moderate drinking of alcohol and some aspect of cognition…Overall, light to moderate drinking does not appear to impair cognition in younger subjects and actually seems to reduce the risk of dementia and cognitive decline in older subjects.”
Bewildered? We don’t blame you. People who drink a lot clearly suffer from serious heart problems, strokes and cancer. They may also develop cognitive decline and possibly Alzheimer’s disease. On the other hand, light alcohol consumption may help the brain.
The Latest Research on Alcohol for Longer Life:
A meta-analysis of nearly 50,000 men and women from the UK suggested that light-to-moderate drinking could reduce the risk of heart attacks, strokes and death in people with diagnosed cardiovascular disease (BMC Medicine, July 27, 2021). Graphing survival against alcohol consumption gave a J-shaped curve, with the lowest risk at 7 g/day of alcohol. A standard drink–a 12-ounce beer or a glass of wine–contains 14 g. Consequently, people who took about half a drink a day achieved the benefits of alcohol for longer life. These data were obtained from the UK Biobank and health surveys from England and Scotland. However, a meta-analysis of a dozen other studies corroborated these conclusions.
Comparing Light and Heavy Alcohol Consumption:
The definition of light alcohol consumption vs. heavy alcohol consumption is critical to the understanding of the seeming confusion. A study published in PLOS Medicine (June 19, 2018) tracked roughly 100,000 people for nearly nine years. Light alcohol drinkers (defined as just one to three drinks a week) were less likely to develop cancer or die prematurely compared to abstainers or “heavy” drinkers. The scientists defined heavy drinkers as those who consumed two to three alcoholic beverages a day. Very heavy drinkers (more than three alcoholic beverages a day) were much more likely to get cancer or die during the study.
The authors concluded:
“The study supports a J-shaped association between alcohol and mortality in older adults, which remains after adjustment for cancer risk. The results indicate that intakes below 1 drink per day were associated with the lowest risk of death.”
The Bottom Line on Alcohol for Longer Life:
A idea of a J-shaped curve is fascinating. In practical terms, it means that people who never drink alcohol have a slightly higher risk of cancer and death than those who indulge occasionally. People who usually consume more than three drinks a day run a much bigger risk. Consequently, the sweet spot seems to be lower alcohol consumption than previously described, namely one to three drinks a week. The data from the UK Biobank study fall within that range, too.