BOSTON -- Athletes suffer concussions all the time. It can happen to professionals, but the dangers are just as real for child and high school athletes when they don't take concussions seriously.

NewsCenter 5's Heather Unruh reported that Chris Nowinski played football and was a superhero of pro wrestling, but eventually all those hits on the field and in the ring caught up to him.

"I got kicked in the chin. By the time I hit the ground, my head was pounding," Nowinski said. "The one before that, I blacked out in the ring. It forced me to quit the WWE."

Nowinski joins a list of professional athletes, such as Patriots Ted Johnson, forced to retire because they brushed concussion symptoms aside. When the athletes continue to play without giving their brains time to heal, they end up suffering brain damage.

"I dealt with terrible headaches, and I still do -- memory problems, depression," Nowinski said.

Nowinski has a new book that warns athletes. Multiple concussions have been linked to depression, dementia and even suicide.

"They don't know they're putting themselves at risk for a much more severe concussion by trying to play through the symptoms," said Emerson Hospital's Dr. Robert Cantu.

Cantu said that he understands the risks, but said parents and athletes need to know, as well.

"The great majority of head traumas that occur on the football fields of this country occur to the approximately 1.25 million high school players who play football," he said.

Common symptoms to look out for include: dizziness, severe headache, vomiting, and confusion and memory loss.

"And then the most serious of them all have to do with cognitive or thought processes, where individuals may have periods of amnesia or they may have difficulty learning new tasks or remember new tasks," Cantu said.

Nowinski said that he wishes he had knew the risks, because for him, the damage has already been done.

"If you play through it you're just going to make it worse. You're not just going to risk your season, you might risk your career. You might risk your life," he said.