Low brain levels of the neurotransmitter GABA are often found in people with depression; SSRIs, electroconvulsive therapy, and now yoga, it seems, can boost GABA. Preliminary research out of the Boston University School of Medicine and Harvard's McLean Hospital found that healthy subjects who practiced yoga for one hour had a 27 percent increase in levels of GABA compared with a control group that simply sat and read for an hour. This supports a growing body of research that's proving yoga can significantly improve mood and reduce the symptoms of depression and anxiety.
Several trials have found that yoga can lower blood pressure, cholesterol, and resting heart rates, and help slow the progression of atherosclerosis—all risk factors for heart disease, says Erin Olivo, PhD, director of Columbia University's Integrative Medicine Program.
While almost any exercise is good for the heart, experts speculate yoga's meditative component may give it an extra boost by helping to stabilize the endothelium, the lining of the blood vessels that, when irritated, contributes to cardiovascular disease. Since the lining is reactive to stress, and meditation can lower stress hormones, yoga may be causing a cascade of events that could reduce your risk of a heart attack or stroke.
Research is becoming clear on this: Women who do yoga during and after treatment experience less physical discomfort and stress. In 2007, Duke University scientists reported results of a pilot study in which women with metastatic breast cancer attended eight weekly yoga sessions. The doctors found that the women had much less pain and felt more energetic and relaxed.
A preliminary study at the University of California, San Francisco, found that menopausal women who took two months of a weekly restorative yoga class, which uses props to support the postures, reported a 30 percent decrease in hot flashes. A four-month study at the University of Illinois found that many women who took a 90-minute Iyengar class twice a week boosted both their energy and mood; plus they reported less physical and sexual discomfort, and reduced stress and anxiety.
Chronic Back Pain
When doctors at the HMO Group Health Cooperative in Seattle pitted 12 weekly sessions of yoga against therapeutic exercises and a handbook on self-care, they discovered the yoga group not only showed greater improvement but experienced benefits lasting 14 weeks longer. A note of caution: "While many poses are helpful, seated postures or extreme movement in one direction can make back pain worse," says Gary Kraftsow, author of Yoga for Wellness, who designed the program for the study.
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