 Yoga as therapy. When is it helpful? As you've seen over the last few videos, the scientific literature on yoga is limited in scope and quality. I've talked about the long list of issues that plague so many of the yoga trials, but let's continue down the list of conditions to get a sense of the best available balance of evidence. For example, yoga as a therapy for irritable bowel syndrome. Students from randomized controlled trials found that yoga beat out drugs and was equally effective as moderate intensity walking, so whichever form of exercise you prefer. What about yoga for inflammatory bowel disease? Since stress can be a trigger, might yoga help? In a trial of yoga as an add-on therapy for adolescents with inflammatory bowel disease, it didn't seem to help at all. But in a trial of yoga versus written self-care advice for adults with ulcerative colitis, 12 weeks of yoga induced a stronger increase in quality of life and also reduced disease activity even three months after the study ended. Here's the graphs for quality of life and disease activity. Now the so-called self-care group was really just handed a couple general self-care books, so the two treatments, yoga versus self-care, were not matched at all for time intensity, feeling part of a group, or for therapist contact, each of which are likely to have the yoga are more likely to non-specifically improve their quality of life. So yes, yoga might be effective in improving quality of life and ulcerative colitis, however the benefits may be no different to other group exercise, for example. Indeed, there have been 11 human studies on the influence of moderate exercise programs upon disease activity and chronic inflammatory bowel disease, and all 11 report benefit in terms of reduced disease activity. Here's an excellent example of why having more active control groups is so important. This details a series of studies on non-pharmacological interventions for menopausal hot flashes. For example, randomized to 8 weeks of acupuncture, 8 weeks of sham acupuncture, or nothing, just usual care. Sham acupuncture is when they still see the results of the patient's behavior, or nothing, just usual care. Sham acupuncture is when they still stick needles in you, but shallowly and not in traditional acupuncture points. There was also a study of 10 weeks of yoga classes, or the attention control health and wellness education classes, which lasted just as long as the yoga and were done in the same kind of group social setting. Here's what they found. The hot flashes in the usual care group, the passive control where they didn't do anything special, stayed pretty stable. But the real acupuncture worked way better, but so did the sham acupuncture. Here's the yoga, and here's the health and wellness classes control group. So, yoga and acupuncture both worked just as well, but so did the non-yoga and fake acupuncture. There just appeared to be a general placebo effect such that women in all 5 intervention groups benefited simply by being in a study. That's why it's always better to have the control groups do something so you can have some confidence at least some of the effect of your intervention is real. But hey, at least they had control groups. This study, 12 minute daily yoga regimen reverses osteoporotic bone loss caused quite a stir. We know that when it comes to bone health, it's use it or lose it. Exercise early and exercise often. Physical activities are widely accessible, low cost and highly modifiable contributor to bone health. Exercise transmits forces through the skeleton, generating signals that are detected by your bone building cells. This is why the National Osteoporosis Foundation, the International Osteoporosis Foundation and other agencies recommend weight-bearing exercises for the prevention of osteoporosis. These include high impact exercises such as jumping, aerobics and running, as well as lower impact exercises such as walking and weight training to create these mechanical signals that spark bone growth. Lower impact activities such as yoga are generally not considered bone building. That's why the results of this study were so surprising. It was a study of internet recruited volunteers comparing bone mineral density changes before and after yoga. The researchers devised a 12 minute DVD of 12 yoga poses that they believed would stimulate increased bone density in the spine and both parts of the hip. Here are the dozen poses and they appeared to get benefit in the spine, but not the hip. But in the end, out of the 741 patients recruited at the beginning, only a few dozen actually sent in their bone scans as instructed. So that's only like 5%. So they lost 95% of the people that originally started. You can totally imagine how those who got positive results were more likely to send them in and the others that failed just kind of slunk away. So I don't consider this convincing evidence. Now the authors had the attitude of, hey look, so what do you got to lose? The side effects of yoga are all good, so why not give it a try? Well, what you have to lose is the opportunity to do higher impact exercise that has more decisive evidence of bone benefit. And all the side effects are not necessarily good. There have been vertebral compression fractures associated with yoga. In this series of 9 cases from the Mayo Clinic, they described spinal compression fractures occurring a month to years after initiating yoga-associated spinal flexion exercises. Both scientific and media reports continue to advertise yoga as a bone protective activity, but there's a need for selectivity in yoga poses in populations that increased fracture risk. Here's the yoga poses they recommend, and these are the ones they encourage people at risk to avoid. And four of the 9 patients developed a fracture in a setting of normal or near normal bone mineral density, so maybe everyone should be careful with these. Yoga-related injuries are not uncommon, resulting in thousands of emergency room visits a year, and approximately 5% of those are coming in with fractures. I'll try to put that injury rate in context comparing yoga to other physical activities. In my final video of the yoga series, next.