Can Yoga Prevent A Cytokine Storm?
Regularly practicing yoga exercises may lower a number of compounds
in the blood and reduce the level of inflammation that normally
rises because of both normal aging and stress, a new study has shown.
In the cases of respiratory infections, cytokines plays a part in
a potentially fatal immune reaction called a "cytokine storm,"
in which the immune system of a healthy person goes haywire and
"overreacts" to an infection. The cytokines command a
patient's body to flood the lungs with fluids and mucous, which
can eventually block off the airways and "drown" the patient.
In a study done by Ohio State University researchers and reported
in the journal Psychosomatic Medicine, they showed that women
who routinely practiced yoga had lower amounts of the cytokine
interleukin-6 (IL-6) in their blood.
The women also showed smaller increases in IL-6 after stressful
experiences than did women who were the same age and weight but
who were not yoga practitioners.
IL-6 is an important part of the body's inflammatory response
and has been implicated in heart disease, stroke, type-2 diabetes,
arthritis and a host of other age-related debilitating diseases.
Reducing inflammation may provide substantial short- and long-term
health benefits, the researchers suggest.
"In addition to having lower levels of inflammation before
they were stressed, we also saw lower inflammatory responses to
stress among the expert yoga practitioners in the study,"
explained Janice Kiecolt-Glaser, professor of psychiatry and psychology
and lead author of the study.
"Hopefully, this means that people can eventually learn
to respond less strongly to stressors in their everyday lives
by using yoga and other stress-reducing modalities."
For the study, the researchers assembled a group of 50 women,
age 41 on average. They were divided into two groups -- "novices,"
who had either taken yoga classes or who practiced at home with
yoga videos for no more than 6 to 12 sessions, and "experts,"
who had practiced yoga one of two times weekly for at least two
years and at least twice weekly for the last year.
Each of the women was asked to attend three sessions in the university's
Clinical Research Center at two-week intervals. Each session began
with participants filling out questionnaires and completing several
psychological tests to gauge mood and anxiety levels.
Each woman also was fitted with a catheter in one arm through
which blood samples could be taken several times during the research
tasks for later evaluation.
Participants then performed several tasks during each visit designed
to increase their stress levels including immersing their foot
into extremely cold water for a minute, after which they were
asked to solve a series of successively more difficult mathematics
problems without paper or pencil.
Following these "stressors," participants would either
participate in a yoga session, walk on treadmill set at a slow
pace (.5 miles per hour) designed to mirror the metabolic demands
of the yoga session or watch neutral, rather boring videos. The
treadmill and video tasks were designed as contrast conditions
to the yoga session.
Once the blood samples were analyzed after the study, researchers
saw that the women labeled as "novices" had levels of
the pro-inflammatory cytokine IL-6 that were 41 percent higher
than those in the study's "experts."
"In essence, the experts walked into the study with lower
levels of inflammation than the novices, and the experts were
also better able to limit their stress responses than were the
novices," Kiecolt-Glaser explained.
The researchers did not find the differences they had expected
between the novices and experts in their physiological responses
to the yoga session.
Co-author Lisa Christian, an assistant professor of psychology,
psychiatry and obstetrics and gynecology, suggested one possible
"The yoga poses we used were chosen from those thought to
be restorative or relaxing. We had to limit the movements to those
novices could perform as well as experts.
"Part of the problem with sorting out exactly what makes
yoga effective in reducing stress is that if you try to break
it down into its components, like the movements or the breathing,
it's hard to say what particular thing is causing the effect,"
said Christian, herself a yoga instructor. "That research
simply hasn't been done yet."
Ron Glaser, a co-author and a professor of molecular virology,
immunology and medical genetics, said that the study has some
fairly clear implications for health.
"We know that inflammation plays a major role in many diseases.
Yoga appears to be a simple and enjoyable way to add an intervention
that might reduce risks for developing heart disease, diabetes
and other age-related diseases" he said.
"This is an easy thing people can do to help reduce their
risks of illness."
Bill Malarkey, an professor of internal medicine and co-author
on the study, pointed to the inflexibility that routinely comes
"Muscles shorten and tighten over time, mainly because of
inactivity," he said. "The stretching and exercise that
comes with yoga actually increases a person's flexibility and
that, in turn, allows relaxation which can lower stress."
Malarkey sees the people's adoption of yoga or other regular
exercise as one of the key solutions to our current health care
crisis. "People need to be educated about this. They need
to be taking responsibility for their health and how they live.
Doing yoga and similar activities can make a difference."
As a clinician, he says, "Much of my time is being spent
simply trying to get people to slow down."
The researchers' next step is a clinical trial to see if yoga
can improve the health and reduce inflammation that has been linked
to debilitating fatigue among breast cancer survivors. They're
seeking 200 women to volunteer for the study that's funded by
the National Cancer Institute.
Researchers Heather Preston, Carrie Houts and Charles Emery were
also part of the research team which was supported in part by
a grant from the National Center for Complementary and Alternative
Medicine, part of the National Institutes of Health.
January 15, 2010