- By Rita Rubin
Downward dogs and cobras could help people recover from cancer and its treatment.
They’re not exotic pets, but rather basic yoga poses, and several studies published in recent months suggest that they can improve the quality of life and perhaps even prolong it for people who’ve had cancer.
Virtually all of the research has focused on breast cancer patients, in part, scientists say, because it’s easier to recruit women into yoga studies. Compared to women who did not practice yoga, those who did experienced reduced inflammation and improved vitality, sleep and physical functioning, the research has found.
While all kinds of exercise have been shown to improve physical and mental health in the general population, there appears to be something special about yoga.
“What yoga has, in addition to the movement, is the meditation and the emphasis on breathing and awareness,” says Janice Kiecolt-Glaser, a professor of psychiatry and psychology at The Ohio State University College of Medicine.
After-Effects and Inflammation
Kiecolt-Glaser is the lead author of a study funded by the National Cancer Institute that randomly assigned breast cancer survivors to either two 90-minute yoga classes per week or a wait list for the classes. The women, who’d been diagnosed with breast cancer at a range of stages, were two months to three years past their last cancer treatment. Women in the yoga group were encouraged to practice yoga outside of the classes, while those on the waitlist were asked not to practice it at all.
The study of 200 women aged 27 to 76, published online Jan. 27 by the Journal of Clinical Oncology, found that after three months of yoga classes, women who’d been participating in them reported higher vitality levels, but not less fatigue, than the wait-listed women. Three months after the classes had ended, though, the women who’d been randomly assigned to the yoga group reported both less fatigue and higher vitality levels than the other women.
Perhaps even more striking, Kiecolt-Glaser and her colleagues found lower levels of markers of inflammation in the blood of women who practiced yoga, both at the end of the three months of classes and three months later. Chronic inflammation is associated with a number of health problems, including heart disease, diabetes and Alzheimer’s. Yoga might have helped the women turn down their response to stress, which can fuel inflammation, Kiecolt-Glaser says.
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Previous studies had suggested that exercise might lower inflammation only in substantially-overweight people, which, on average, the participants in this study were not, she says. “Part of the reason I think we saw reductions in inflammation is that we started out in a group that had higher levels of inflammation,” she adds.
Improved sleep could be one reason the yoga group fared better than the waitlist group, Kiecolt-Glaser says. That notion is supported by research published last September by the Journal of Clinical Oncology. In that study, 410 cancer survivors around the country were randomly assigned to standard care or standard care plus two 75-minute yoga sessions a week for four weeks.
As in Kiecolt-Glaser’s study, participants had completed their cancer treatment at least two months earlier. However, this study included several male cancer survivors and a quarter of the women who participated had been treated for malignancies other than breast cancer. The researchers found that yoga helped improve sleep quality and reduce sleep medication use.
Lead author Karen Mustian, an associate professor in the departments of surgery and radiation oncology at the University of Rochester School of Medicine and Dentistry, says she’d next like to compare yoga to cognitive behavioral therapy for insomnia, a common problem in cancer patients and survivors. Cognitive behavioral therapy is usually conducted one-on-one with a clinical psychologist and covers steps that can improve sleep, such as not watching television or eating in bed.
“We don’t really understand the mechanisms of sleep,” says Mustian, whose training is in exercise physiology. “Yoga is an interesting intervention. If you talk to some people, they consider yoga a form of exercise. Then some people would say, 'No, not really.'”
People feel different after a yoga class than they do after, say, walking on a treadmill, she notes. They’ll say, “I feel so much more relaxed. I feel so much more grounded.”
Comparing Yoga and Other Exercise
Another recent study provides evidence that not just any type of exercise would be as beneficial as yoga for cancer patients.
MD Anderson Cancer Center researchers compared yoga to stretching exercises as well as to a waitlist group. The Houston scientists collaborated with India's largest yoga research institution, Swami Vivekananda Yoga Anusandhana Samsthana in Bangalore.
The researchers recruited 163 breast cancer patients who were about to begin radiation therapy. They were randomly assigned to yoga or stretching exercises three times a week for six weeks or to a waitlist. Participants received daily radiation treatment, which is associated with fatigue, during the six weeks.
While both the stretching exercises and yoga helped reduce fatigue, only women in the yoga group experienced an improved ability to perform daily activities and better overall health, the researchers reported in a paper published online March 3 in the Journal of Clinical Oncology. In addition, improved regulation of the stress hormone cortisol was observed only in the yoga group. That could improve sleep.
Finding Meaning in Illness
“What we saw in our paper by and large was a physical benefit” of yoga, says co-author Dr. Lorenzo Cohen, professor and director of the Integrative Medicine Program at MD Anderson. However, he says, another finding they have not yet reported was “an improvement in the ability to find meaning in the illness experience.”
So, apparently, Cohen says, the controlled breathing, quiet meditation and other aspects of mindfulness — or living in the moment — that yoga incorporates make it more beneficial than exercise that does not involve them.
If you’re a cancer survivor who’s interested in taking yoga classes, you should thoroughly vet prospective teachers, Mustian says. Ask them whether they’ve ever worked with cancer patients and what kind of cancer they had; see if you can observe a class or two.
After checking out all the professional yoga organizations in the U.S., Mustian says, she decided to enlist in her study only teachers who’d been credentialed by the Yoga Alliance: “They’re in most communities, and they’re very easy to find.”
And you don’t have to be a cancer patient or survivor to benefit from yoga, which at the very least improves flexibility, Mustian, Cohen and Kiecolt-Glaser agree.
All three practice yoga. Kiecolt-Glaser started it on the advice of a physician friend in his mid-70s who told her, “You never want to be one of those older people who can’t cut their own toenails.”
Rita Rubin is a former USA Today medical writer who now writes about health and science for publications including Next Avenue, WebMD and NBCNews.com.