There have been many studies showing both positive and negative benefits of alcohol consumption, with more of the beneficial studies centering around moderate consumption compared with heavier consumption. Depending upon the definition of “moderate”, even within the moderate consumption “level”, studies have been inconsistent in terms of their findings in relation to human health.
The exact mechanism for supposed health benefits of moderate alcohol consumption is so far unknown, though theories do exist.
Some observed health benefits of moderate alcohol consumption
include: reduced risk of cardiovascular diseases, and in general all-cause mortality. High levels of the antioxidant bilirubin have been observed in people with reduced risk of cardiovascular disease and all-cause mortality, begging the question whether or not moderate alcohol consumption could be at least partially responsible for this increase.
A new study accepted into the journal Drug and Alcohol Dependence aimed to examine bilirubin levels after alcohol consumption, in an attempt to create a possible mechanistic link between moderate alcohol consumption and reduced risk of cardiovascular disease and all-cause mortality.
18 healthy adults (8 smokers) were given alcohol to achieve blood alcohol levels of 20, 80, and 120mg/dL in random order during three sessions separated by one week each time.
Serum bilirubin levels were measured in the morning before the drinking session, at 2pm the day of the drinking session, and in the morning the day after the drinking session.
Serum bilirubin levels increased from baseline to 24 hours post drinking in non-smokers.
Serum bilirubin levels DID NOT increase after drinking in smokers.
The results of this study suggest a possible mechanism for reduced risk of cardiovascular disease and all-cause mortality after moderate alcohol consumption in non-smokers. For non-smokers, serum bilirubin levels increased, resulting in possible anti-oxidant protection properties for these improved health benefits.
Smokers, on the other hand, were not so lucky, as serum bilirubin levels remained unchanged after moderate alcohol consumption.
Smoking somehow prevented serum bilirubin levels from increasing, thus negating any possible health benefit of moderate alcohol consumption caused by increased bilirubin levels in the blood.
This study only followed 18 adults, therefore follow up studies with larger sample sizes are required to confirm or refute this possible mechanistic link between moderate alcohol consumption, increased serum bilirubin levels, and reduced risk of cardiovascular diseases and all-cause mortality.