Past studies have shown moderate drinking can improve cardiovascular function and even reduce the risk death overall; new research suggests the lifestyle choice could also give the immune system a boost.
A research team gave rhesus macaques, a primate that has an immune system similar to humans, alcohol that consisted of four percent alcohol, an Oregon Health and Science University news release reported.
The macaques were separated into two groups; one was given unlimited access to the alcohol and the other to sugar water. Both groups were vaccinated for small pox and had regular access to food and water.
The team analyzed the monkeys for a total of 14 months; and the study subjects were re-vaccinated seven months into the experiment.
"Like humans, rhesus macaques showed highly variable drinking behavior," Ilhem Messaoudi, the lead author of the paper, a former assistant professor at the Vaccine and Gene Therapy Institute at OHSU and assistant scientist in the Division of Pathobiology and Immunology at the Oregon National Primate Research Center, who now works as an associate professor of biomedical sciences at the University of California, Riverside, said. "Some animals drank large volumes of ethanol, while others drank in moderation."
The alcohol-drinking monkeys were classified into two groups; the "heavy drinkers" and the "moderate drinkers."
The heavy drinkers had a blood alcohol level of about 0.08 percent; this is the legal limit for driving. The moderate drinkers had an average blood alcohol level of 0.02 to 0.04 percent.
At the beginning of the study both the alcohol and sugar water groups had similar responses to the smallpox vaccine; but something changed once the subjects started consuming alcohol.
The "heavy drinking" monkeys showed a diminished response to the vaccine when compared with the control group, but the "moderate drinkers" showed a greater immune response to the vaccine.
"It seems that some of the benefits that we know of from moderate drinking might be related in some way to our immune system being boosted by that alcohol consumption," Kathy Grant, Ph.D., senior author on the paper, a professor of behavioral neuroscience at OHSU and a senior scientist at the ONPRC, said.
The researchers hold that excessive alcohol consumption can harm one's health.
"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," Messaoudi said. "But for the average person who has, say, a glass of wine with dinner, it does seem in general to improve health and cardiovascular function. And now we can add the immune system to that list."
