Many of us enjoy a drink or two to celebrate the festive season. And now, researchers say the odd glass of wine with dinner may actually benefit our health - as new research suggests it can boost the immune system and improve its response to vaccination.
This is according to findings published in the journal Vaccine.
The study researchers, led by Ilhem Messaoudi of the School of Medicine at the University of California, Riverside, say their research may help lead to a better understanding of how the immune system works, and how to improve its ability to respond to vaccines and infections.
To reach their findings, the researchers trained 12 monkeys (rhesus macaques) to consume alcohol freely.
Beneficial in small doses: researchers say moderate alcohol consumption, such as a glass of wine with dinner, may help boost the immune system and its response to vaccinations.
Prior to this, the monkeys were vaccinated against smallpox. One group of the monkeys was then allowed access to either 4% alcohol, while the other group had access to sugar water. All monkeys also had access to normal water and food.
The monkeys were then monitored for a 14-month period and were vaccinated again 7 months into the experiment.
During this time, the investigators found that the monkeys' voluntary alcohol intake varied, just as it does in humans. This led the investigators to divide them into two groups.
The first group consisted of monkeys that were "heavy drinkers" - defined as having a blood ethanol concentration (BEC) more than 0.08%. The second group was deemed "moderate drinkers," with a BEC of between 0.02-0.04%.
Moderate alcohol consumption 'enhanced vaccine response'
The researchers found that before the monkeys had free access to alcohol, they all demonstrated comparable responses to the vaccinations. But after alcohol consumption, they all showed different vaccine responses.
The monkeys classed as heavy drinkers showed diminished responses to the vaccine, compared with the monkeys that consumed sugar water. But the investigators were surprised to find that the monkeys deemed as moderate drinkers demonstrated an enhanced vaccine response.
Commenting on the findings, Messaoudi says:
"These surprising findings indicate that some of the beneficial effects of moderate amounts of alcohol consumption may be manifested through boosting the body's immune system.
This supports what has been widely believed for some time: moderate ethanol consumption results in a reduction in all causes of mortality, especially cardiovascular disease. As for excessive alcohol consumption, our study shows that it has a significant negative impact on health."
A glass of wine with dinner 'could improve health'
According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), moderate drinking is defined as no more than four alcoholic drinks on any single day for men and no more than 14 in total over a week. For women, this reduces to three drinks on any single day and no more than seven drinks over a week.
The researchers emphasize that although their research suggests moderate alcohol consumption may benefit the immune system, they do not recommend that people with a history of alcohol abuse start to drink based on these findings.
"If you have a family history of alcohol abuse, or are at risk, or have been an abuser in the past, we are not recommending you go out and drink to improve your immune system," says Messaoudi.
"But for the average person that has, say, a glass of wine with dinner, it does seem, in general, to improve heath, and cardiovascular function in particular, and now we can add the immune system to that list."
Messaoudi adds that the team plans to further investigate how immune system responses to vaccinations can be boosted using these findings.
They add that they will focus on how this can be done in vulnerable populations, such as the elderly, who are often known to have ineffective vaccine responses.
This is not the first study to show the potential benefits of moderate alcohol consumption. Earlier this year, Medical News Today reported on a study suggesting that consuming a glass of wine a day may reduce the risk of depression, while other research suggests a compound found in red wine could help treat cancer.