We’ve all heard it before: Moderate consumption of alcohol is beneficial to your health. From lowering mortality risk to providing antioxidants and protein, wine, beer, and even hard liquor can be beneficial, as long as it’s not overdone. Adding to that list, new research now shows that moderate alcohol consumption — for primates, at least — might even reinforce the immune system’s response to vaccines, allowing them to be more effective.

Although the findings have widespread implications, the researchers believe that they will primarily benefit vulnerable populations, such as the elderly, who have difficulty responding to the flu vaccine — 90 percent of flu-related deaths occur in people over 65 years old. For this reason, many elderly people have the option of taking a high-dose shot, meant to improve immune response. The researchers believe, however, that moderate consumption — about four drinks per week — can have a similar effect.

“It has been known for a long time that moderate alcohol consumption is associated with lower mortality,” Ilhem Messaoudi, associate professor of biomedical sciences at the University of California, Riverside, School of Medicine, said in a press release. “Our study, conducted on non-human primates, shows for the first time that voluntary moderate alcohol consumption boosts immune responses to vaccination.”

The study, which was published in the journal Vaccine, involved training 12 rhesus macaques to drink alcohol on their own. The researchers then gave them smallpox vaccines, and made available either four percent ethanol — the active ingredient in alcoholic beverages — or a calorically-matched sugar water. All the animals also had access to water as well, which allowed them to develop their own drinking habits, with some drinking alcohol more than others.

Seven months later, the macaques were given booster shots. At nine months, the researchers were able to distinguish those macaques that were heavy drinkers — blood ethanol content (BEC) over 0.08 percent — and those who were moderate drinkers (BEC of 0.02 to 0.04). At 14 months, they found that those macaques that were heavy drinkers showed significantly worse immune responses to the vaccine when compared to the control group. However, they also found that moderate drinking was associated with an enhanced response.

“These surprise findings indicate that some of the beneficial effects of moderate amounts of alcohol consumption may be manifested through boosting the body’s immune system,” Messaoudi said in the press release. “This supports what has widely been believed for some time: moderate ethanol consumption results in a reduction in all causes of mortality, especially cardiovascular disease … For the average person that has, say, a glass of wine with dinner, it does seem, in general, to improve health.”

Source: Messaoudi I, Asquith M, Engelmann F, et al. Moderate alcohol consumption enhances vaccine-induced responses in rhesus macaques. Vaccine. 2013.