Moderate alcohol consumption linked to multiple health benefits
These effects include cognitive impairment, neurotransmitter imbalances, brain atrophy, loss of neurons — which leads to impairments in conscious thought — decreases in white and gray matter volume, and the increased risk of developing dementia.
The report then goes on to state that previous studies, such as the U.S. National Library of Medicine’s “Brain gray and white matter volume loss accelerates with aging in chronic alcoholics: a quantitative MRI study” and “Effects of alcoholism and continued abstinence on brain volumes in both genders” have confirmed alcohol’s negative effects.
However, there are also numerous studies that tout the benefits of low levels of alcohol. Studies such as “Alcohol and mortality: a U-shaped curve” and “Do ‘Moderate’ Drinkers Have Reduced Mortality Risk? A Systematic Review and Meta-Analysis of Alcohol Consumption and All-Cause Mortality” from the National Library of Medicine reveal that moderate alcohol consumption leads to reduced risk of cardiovascular diseases.
Moderate consumption also reduces the risk for a number of cancers and increases cerebral circulation, or the movement of blood through the chain of blood vessels furnishing the brain.
Overall, the study adopts the idea that the effects of alcohol follow a J-shaped curve, with alcohol being good in small amounts but detrimental in larger doses.
The study also highlights the recent discovery of the highly organized system of cerebrospinal and interstitial fluid known as the glymphatic system. This system of the body is responsible for clearing the fluids in the central nervous system of waste products and metabolites. These molecules are then flushed into the lymphatic system so they can be taken to other parts of the body, mainly the liver, to be ultimately degraded.
The glymphatic system serves a key role in the clearance of potentially neurotoxic proteins including those of the beta-amyloid and tau varieties, which are known to be key contributors to certain neurological disorders such as Alzheimer’s disease.
The study was conducted using mice that consumed either acute or chronic amounts of alcohol, followed by 24 hours of withdrawal. Glymphatic function was then measured and it revealed unexpected results.
The study found that acute alcohol intake potently altered glymphatic function in the awake stage depending on the dosage consumed. Meanwhile, intermediate alcohol exposure, corresponding to about 7.9 drinks a day, lowered glymphatic function, although this was not an irreversible effect.
Regular glymphatic function was restored within 24 hours after the mice were stopped from consuming excessive amounts of alcohol. A very high dose of alcohol, equivalent to 21 drinks a day, also resulted in a severe reduction of glymphatic function.
Low level exposure to alcohol, equal to two and a half drinks per day, actually resulted in a boost of glymphatic function due to the combination of both increased cerebrospinal fluid tracer influx and more robust reduction of cerebrospinal fluid tracer.
The data provided by the study models the previous notion of alcohol’s J-shaped curve of benefits as a function of alcohol consumption.
Low to moderate consumption is often associated with a decreased risk of dementia, while heavy drinking confers a higher risk of cognitive decline.
One possible explanation that the study proposes is that the alcohol reduces neuroinflammation caused by a sedentary lifestyle, as the mice were deprived of a running wheel in their housing environment.
The Rochester study adds more to a question that has troubled humans for a long time: the benefits and disadvantages of humanity’s secondary drug of choice after coffee.
The study itself seeks to wrestle with this question by weighing some of the benefits revealed by the experiment against health issues that may arise from drinking a similar amount. For example, the study notes that, “Daily intake of alcohol for 30 years at doses scalable to those in the present study reduces human hippocampal volume by 3.4–5.8 percent compared to abstainers,” indicating that the low dosage level group would eventually discover more issues with alcohol than benefits.
The study also warns readers that “this study performed on mice should not be viewed as a recommendation for alcohol consumption guidelines in humans.”
Baruch students seem to echo the worries of the experiment’s researchers. Justin Bischof, a freshman and prospective actuarial science major, said that he “can see the benefits of having a glass of wine with dinner because of antioxidants and all that other stuff. However, two and a half drinks a day seems like too much.”
Despite all of the studies conducted on the use and misuse of alcohol, it remains a hotly discussed substance in the world of science, and should still be consumed with caution.