Repeated bumps to the head are bad for children. This sounds incredibly obvious, yet as a society, we don’t particularly act like we get it at all.

When the Bruins made it into the Stanley Cup finals, I thought about all the young hockey players who would be inspired to practice harder and play harder in the hope of one day doing the same. And I wondered: if they bumped their head hard enough in a practice or game to get a concussion, would they be willing to stop playing–for maybe even a year?

My colleagues at Boston Children’s Hospital just published a study showing that children take longer to recover from a concussion if they’ve had one or more previous concussions. If they haven’t had a concussion in a year or more, though, their recovery time was the same as someone who had their first concussion.

Now, this study just looked at recovery time, not long-term effects of concussion. But if it takes you longer to recover, that means that things are still healing and not back to normal. And plenty of studies suggest that repeated blows to the head do lead to permanent brain damage. We know that hockey is one of those sports that carries a higher risk of concussion than other sports. You can try to cut down the risk with safety gear and safety rules, but you can’t make the risk low.  So, if you send your kid back to hockey practice within a year after a concussion, you are risking brain damage.

I’m going to guess that lots of parents (perhaps most of them) wouldn’t keep their kids out of hockey (or football or lacrosse or other high-risk sport) for a year after a concussion. They would take the risk. They wouldn’t want their kid to miss out — for all sorts of reasons. Some of those reasons might be good ones, but some are less good — like the ones having to do with achievement, or culture. That’s the conversation we need to have.

Don’t get me wrong: I’m a big fan of youth sports — all of them. Sports keep kids healthy and out of trouble, and the lessons and habits learned from youth sports can help kids grow into healthy adults. I know that we can’t keep kids in bubbles, and that accidents happen. But the fact that we are seeing more and more concussions in youth sports — and that we are sending kids back in to play afterward — is something that demands some soul-searching.

Youth sports should be about fun, exercise and building healthy habits for a lifetime. It should never involve knowingly risking brain damage. We owe our children more than that.

Claire McCarthy is a primary care physician and the medical director of Boston Children’s Hospital’s Martha Eliot Health Center.  She blogs at Thriving, the Boston Children’s Hospital blog, Vector, the Boston Children’s Hospital science and clinical innovation blog, and MD Mama at Boston.com, where this article originally appeared.