Moderate Alcohol Consumption Boosts Body's Immune System, Study Suggests
Medical science has known
for years that people who drink moderate amounts of alcohol actually have a
reduced risk of death. In general, they are healthier and have better
cardiovascular function that those who don't drink alcohol at all.
Now, new research from
Oregon Health & Science University adds a fascinating twist: moderate
drinking may actually bolster our immune system and help it fight off
infection.
The research, published
Dec. 17 in the journal Vaccine,
not only opens a new window into scientific understanding of the immune system,
it also could help scientists find new ways to improve the human body's ability
to respond to vaccines and infections.
Researchers vaccinated
the monkeys against small pox as part of the study. They then separated the
animals into two groups -- those with access to the 4 percent ethanol and those
with access to sugar water. All of the animals had regular access to pure
water, and to food.
The researchers then
monitored the animals' daily ethanol consumption for 14 months. And the animals
were vaccinated again, seven months after the experiment began.
"Like humans, rhesus
macaques showed highly variable drinking behavior," said 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 and
now an associate professor of biomedical sciences at the University of
California, Riverside. "Some animals drank large volumes of ethanol, while
others drank in moderation."
The monkeys' voluntary
ethanol consumption segregated them into two groups. One group was made up of
heavy drinkers, those that had an average blood ethanol concentration greater
than 0.08 percent -- the legal limit for humans to be able to drive a vehicle.
The other group was made up of moderate drinkers, with an average blood ethanol
concentration of 0.02 to 0.04 percent.
Prior to consuming the
alcohol, all of the animals showed comparable responses to the vaccination. But
after exposure to the alcohol, the two groups of monkeys responded in very
different ways to the vaccination.
The heavy drinkers showed
greatly diminished vaccine responses compared with the control group of monkeys
who drank the sugar water. But the more surprising finding: the
moderate-drinking monkeys displayed enhanced responses to the vaccine compared
to the control group. Moderate drinking bolstered their bodies' immune systems.
"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," said Kathy Grant, Ph.D.,
senior author on the paper, a professor of behavioral neuroscience at OHSU and
a senior scientist at the ONPRC.
The researchers stressed
that excessive alcohol consumption was injurious to the monkeys' immune systems
-- just as excessive alcohol consumption is bad for human bodies in many ways.
"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."
The next steps for the
researchers will be to better understand why the immune system reacts as it
does to moderate alcohol. That may lead to a pharmaceutical alternative that
could provide the same benefits as the moderate alcohol consumption.
Story Source:
The above story is based
on materials provided by Oregon Health & Science University.
Note: Materials may
be edited for content and length. For further information, please contact the
source cited above.
Journal Reference:
1.
I. Messaoudi, M. Asquith, F. Engelmann, B. Park, M. Brown, A. Rau,
J. Shaw, K.A. Grant. Moderate
alcohol consumption enhances vaccine-induced responses in rhesus macaques. Vaccine, 2013; 32 (1): 54
DOI:10.1016/j.vaccine.2013.10.076
