Wines, beers, and liquor are staples in many social traditions, but excessive alcohol consumption can have serious adverse effects on health. (1) Despite these risks, some argue that moderate drinking may offer certain health benefits compared to complete abstinence, often citing scientific studies and the so-called J-shaped curve as evidence. (2)
A recent study challenges this perspective, sparking widespread discussion about its implications. Dr. Layne Norton, who holds a PhD in Nutritional Sciences, analyzed this study alongside others that examine the pros and cons of alcohol consumption.
[Related: Red Meat: Friend or Foe For Your Gut?]
A New Meta-analysis
The study examined the relationship between alcohol consumption and mortality risk, addressing several limitations found in previous research. (3) Notably, it used lifelong non-drinkers as the control group to ensure more accurate comparisons. Common issues in earlier studies included:
- Including former drinkers who may have previously consumed alcohol moderately or heavily and stopped for health reasons. These individuals could still carry underlying health problems caused by years of drinking, skewing results.
- Accounting for participants’ socioeconomic status and age, factors that can significantly influence health outcomes.
- Considering smoking status is a key variable given its strong link to higher mortality risk.
Addressing these factors, the study aimed to provide a more robust and reliable analysis of alcohol consumption’s impact on mortality.
Results
This new study conducted various analyses, many of which found a reduced risk of mortality associated with low-to-moderate alcohol consumption. “Low-moderate means anywhere from one drink per week up to two drinks per day,” Dr. Norton stated. “When I say drinks, they’re looking at ethanol intake from 25 to 40 grams.”
Initial findings showed a reduction in mortality risk ranging from 10% to 15%. The reduction shrank significantly after adjusting for age, smoking status, abstinence, and other variables. The adjusted risk dropped to just 5%.
Smoking Status and Alcohol Intake
The study found no significant increased risk of mortality associated with low-to-moderate alcohol consumption. However, non-smokers who drank at these levels faced a 16% higher risk of mortality compared to lifelong abstainers.
Among smokers, low-to-moderate alcohol consumption was linked to a 7% lower mortality risk compared to those who never drank. Dr. Norton emphasizes that these percentages are not statistically significant, highlighting the need for cautious interpretation.
Dose-Response Curves (J-shaped or Not)
Researchers conducted two dose-response analyses to examine the effects of increasing alcohol consumption. High-quality studies accounted for confounding variables in one analysis, while the other did not.
The uncorrected analysis displayed the familiar J-shaped curve observed in previous studies. The corrected analysis revealed a different pattern: a flat response at lower intake levels, followed by a linear increase in risk for moderate to heavy drinkers.
Take Away
Dr. Norton asserted that alcohol offers no health benefits and is not health-promoting, even in low or moderate amounts. However, the body is equipped with mechanisms to process and eliminate alcohol, provided consumption stays within manageable limits.
“If you’re drinking enough to get drunk, drinking enough to where ethanol is in your bloodstream, and you’re probably getting some of the negative health outcomes,” Dr. Norton addressed.
Dr. Norton made clear that he isn’t encouraging alcohol consumption but acknowledges that drinking plays a significant role in many cultures and is often a way people connect socially. Excessive alcohol intake, defined as more than three drinks per day, can increase the risk of mortality by 50%.
For those who enjoy drinking, there may be a moderate amount that can be consumed without leading to long-term health consequences. “It’s probably a very small amount, and many people probably exceed that,” Dr. Norton exclaimed. “Once you get past that moderate amount, it is a linear increase and risk based on your exposure to alcohol.”
References
- Varghese, J., & Dakhode, S. (2022). Effects of Alcohol Consumption on Various Systems of the Human Body: A Systematic Review. Cureus, 14(10), e30057. https://doi.org/10.7759/cureus.30057
- Visontay, R., Mewton, L., Sunderland, M., Chapman, C., & Slade, T. (2024). Is low-level alcohol consumption really health-protective? A critical review of approaches to promote causal inference and recent applications. Alcohol, clinical & experimental research, 48(5), 771–780. https://doi.org/10.1111/acer.15299
- Stockwell, T., Zhao, J., Clay, J., Levesque, C., Sanger, N., Sherk, A., & Naimi, T. (2024). Why Do Only Some Cohort Studies Find Health Benefits From Low-Volume Alcohol Use? A Systematic Review and Meta-Analysis of Study Characteristics That May Bias Mortality Risk Estimates. Journal of studies on alcohol and drugs, 85(4), 441–452. https://doi.org/10.15288/jsad.23-00283
Featured image via Shutterstock/PeopleImages.com – Yuri A
