Some forms of yoga can be good for some people. And some of them can be quite bad, which isn't often acknowledged. There's a lot of dogma in the yoga community. See the New York Times article How Yoga Can Wreck Your Body [1] and the followup discussion
The Healing Power of Yoga Controversy [2].
[1] http://www.nytimes.com/2012/01/08/magazine/how-yoga-can-wrec...
[2] http://6thfloor.blogs.nytimes.com/2013/01/10/the-healing-pow...
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