Nov 5, 2015

Is yoga bad for you? Here's what the evidence says.

Julia Belluz
November 4, 2015

This is the type of yoga pose you shouldn't do if you're a beginner.
This is the type of yoga pose you shouldn't do if you're a beginner.

Dear Julia: I've heard I'm wrecking my body with yoga. Is that true?

No, probably not.

Many aspiring yogis have been worried about this question ever since the New York Times ran a feature in 2012 suggesting that yoga can ruin your back or (in rare situations) even kill you.

But that piece was largely based on cherry-picked anecdotes, exaggerating the worst-case examples and suggesting they were representative of the broader yoga experience when they simply aren't. (Here's a roundup of the best critiques of that story.) When scientists have looked into this question, they've found that yoga is generally safe.

I spoke to Holger Cramer, the director of yoga research at the University of Duisburg-Essen in Germany, for a broader review of the scientific evidence on yoga. He has extensively studied reports of injuries and other harms from yoga, and he drew this conclusion: "We found yoga is as safe as any other activity. It's not more dangerous than any other form of exercise."

Lorenzo Cohen, chief of the integrative medicine section at MD Anderson Cancer Center, concurred with this take: "There can, of course, be negative consequences if done incorrectly, like any body manipulation," he said, "but if you have the right teacher, this will not happen."

Let's look at the evidence. In a 2013 review, Cramer identified 76 unique incidents of "adverse events" from yoga — documented case studies where things went wrong. "Most adverse events affected the musculoskeletal, nervous, or visual system," he concluded. "More than half of the cases for which clinical outcomes were reported reached full recovery, 1 case did not recover at all, and 1 case died."

Most often, Cramer found, people got into trouble with the headstand pose. Also causing adverse events were: the shoulder stand, postures that required putting one or both feet behind the head, the lotus position, and forceful breathing. Pranayama-, hatha-, and Bikram-style yoga practices had the most adverse events associated with them. 

Cramer and his co-author had practical advice for how to stay safe in yoga: Beginners should avoid advanced postures (such as headstands), and people with chronic health conditions (such as glaucoma) should consult their doctors before diving in. "Yoga," they also advised, "should not be practiced while under the influence of psychoactive drugs."

So the odds of injury are low. But what about long-term effects? Here, the evidence is pretty thin. Cramer pointed to two studies on joint and cervical disc degeneration in people who have been doing yoga for a while. Those studies had contradictory results, and he says that "long-term health consequences cannot be clearly derived from the available evidence." We also don't yet have a good sense for how the long-term impacts, both good and bad, compare with those from other forms of exercise, such as running or weightlifting.

It's possible that adverse yoga events are underreported, but probably no more or less so than for any other activity, and this method of reviewing injury case reports is generally accepted as sound. So based on the evidence we do have, the balance suggests that yoga is about as safe as any other exercise. Just make sure you have a good teacher and don't do headstands or other more advanced contortions before you're ready. Injuries are always a possibility, as they are with any physical activity, but that always has to be weighed against the benefits — and, in the case of yoga, there's good evidence that it can alleviate lower back pain, reduce inflammation, and boost overall health. 

For a fuller picture of yoga's pros and cons, read our evidence review.

Welcome to Dear Julia, a weekly column where readers can submit everyday health questions. Which over-the-counter painkillers work best? Is it better to run or walk for exercise? How much harm does frequent flying do to your body? Julia Belluz will sift through the research and consult with experts in the field to figure out how science can help us live happier and healthier lives.

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