By Erika von Tiehl

PHILADELPHIA (CBS) — Have you heard yoga can be dangerous? It’s a intense debate raging nationwide. 3 On Your Side Eyewitness News anchor Erika von Tiehl examines the controversy.

It’s supposed to be good for you, improve strength and flexibility, and reduce stress. But is yoga riskier than it looks?

William Broad, a New York Times science writer, is blunt: “People die from doing yoga.”

Broad, who does yoga himself, was shocked to find out that popular moves can cause serious injuries. His New York Times article “How Yoga Can Wreck Your Body” hit like a bomb.

“Asking a yoga teacher whether this discipline is likely to cause injuries is sort of like asking Philip Morris whether cigarettes might cause cancer,” said Broad.

Broad says he found case after case of injuries blamed on yoga: dislocated hips, punctured lungs, back problems. Some cases came up over time. Others popped up quickly.

Broad’s research suggests that postures that bend the neck, such as headstand, shoulder stand and plow, are particularly risky.

“There are arteries that go through vertebrae,” Broad explained, “and you start scrunching around with them, and you start getting clots, and those clots go to the brain. Presto chango, you’ve got a stroke.”

Dr. Haemi Choi has never seen injuries that serious, but she herself strained her back when she tried an advanced yoga class as a beginner.

“I was trying to copy those moves, and I know I probably wasn’t doing in the proper form,” said Dr. Choi. “I strained my back while I was doing an upward-facing dog after doing all those other moves beforehand.”

Another yoga teacher hurt herself as a beginner.

“I popped out the back of my knee in a very hot room, and I was over-flexible and hyperextended,” she said.

At the Cherry Hill Health and Racquet Club, yoga instructor Louisa Bosco says she has never had a student injured.

“I am a believer that if you get injured, you moved beyond your capability and beyond your strength,” said Bosco.

Broad still believes in the power of yoga, but he hopes the yoga world finds better and safer moves.