A research group, led by a University of California, Riverside, immunologist, found that moderate alcohol consumption, such as a daily glass of wine, can boost the immune system, potentially helping people fight infections.
The knowledge could be used to improve reactions to vaccines and infections, according to a news release.
For example, even though elderly patients may receive a flu vaccine, it remains relatively ineffective.
Scientists already have found that moderate alcohol consumption has been associated with lower mortality.
Using a dozen rhesus monkeys, the research group studied the effects of alcohol consumption on the immune system.
The monkeys were trained to consume alcohol when they wanted.
The researchers initially vaccinated the animals against small pox. The test group was provided access to either 4 percent ethanol, which has a similar proof to beer, while the control group had access to calorically matched sugar water. Both groups also had access to plain water.
The researchers monitored the animals for 14 months. At month seven, they vaccinated the animals again.
During nine months of the animals' self-administered alcohol consumption, daily intake varied widely.
Before consuming alcohol, all of the monkeys' responses to vaccination were similar.
Following alcohol consumption the groups showed markedly different responses after receiving the second, or booster, vaccine.
Similar to human counterparts, monkeys that drank the largest amounts of alcohol had greatly diminished vaccine responses compared to the control group.
But those that drank moderate amounts of alcohol had enhanced vaccine responses.
“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,” Ilhem Messaoudi, an associate professor of biomedical sciences and lead author, said in the release.
“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.”