We need to figure out what kind of damage football is doing to players' brains
But we know that some have suffered from brain injuries as a result of those batterings, and we know that concerns about those brain injuries are growing to the point that many are starting to question the safety of playing the sport at all.
Earlier in March, we found out that San Francisco 49ers linebacker Chris Borland retired from the sport at the age of 24, citing concerns about head injuries.
"I just want to live a long healthy life, and I don't want to have any neurological diseases or die younger than I would otherwise," he said.
Borland has legitimate reasons to be concerned. He cited the cases of Mike Webster, Dave Duerson, and Ray Easterling, players famously diagnosed after their death with a condition that causes a breakdown in the brain known as chronic traumatic encephalopathy, or CTE. The repeated blows to the head those men suffered throughout their careers is what medical professionals say is most likely responsible for the brain condition that caused them intense suffering to the point of breakdown and - in at least in two of the three cases - ended in suicide.
But we don't know nearly enough about CTE right now, and that needs to change, according to an editorial published by researchers Chad Asplund and Thomas Best in the medical journal BMJ on March 24.
Long term studies into what exactly is happening to players' brains are needed so we can find out "if brain damage is an inevitable consequence or an avoidable risk in American football," they write. There haven't been any of those long term studies of CTE so far.
If brain damage in an inevitable consequence, that's something that people who play the sport should know. And if there's a way to avoid or minimize the risk of brain damage and we ignore that because we don't study it, that's just unacceptable.
Until very recently, the researchers note, the NFL denied any possible link between football and brain injuries or CTE - last year they finally reversed course and settled a lawsuit by former NFL players who attribute their neurological problems to their time in the league for more than $765 million, though details are still being worked out.
And while that money may help some of those players it won't do anything for players who played throughout their youth and through college but didn't make it into the NFL. Non-professionals can still suffer from the symptoms associated with CTE. The New York Times profiles one such player, Ryan Hoffman, a former UNC lineman who is now homeless and struggles with depression, substance abuse, and short-term memory problems.
When looking at a case like Hoffman's, it makes you wonder whether football should be played at all - and I write that as a football fan who's very conflicted about this.
At this point no one can even say if Hoffman has CTE, but his symptoms are consistent. It currently can't be diagnosed until after death, something that doesn't help that former player who now has impulse-control problems, aggression issues, and can't hold a job.
The researchers write that autopsies have only confirmed 63 cases of CTE in football players, a tiny fraction of all those that have played the game - though other cases and neurological problems could easily have gone undiagnosed. (More recent estimates put the number of CTE cases in football players at more than 70.)
And while some argue that the small number of cases means that football's risks are overblown, CTE is a real thing and it seems to have been caused by playing football.
Researchers say that factors like substance abuse, genetic risk, and other biological factors are not the cause of the brain condition. Not even all the players shown to have had CTE had a history of concussion - the only factor they all had in common was "a history of repetitive blows to the head." The question that needs to be answered is just how dangerous those blows to the head are.
But even now, the NFL is slow to study head injuries. They suspended a pilot program this year that would use helmet sensors to assess the impacts of blows to the head during games, citing concerns about accuracy and privacy.
There are complications in judging football based on numbers. As Dan Engber of Slate points out, we may know that more than one in four football players will suffer from cognitive decline or brain diseases like Alzheimer's, but players also tend to live longer than the average person, which might explain the fact that large numbers eventually suffer from those diseases.
Still, we should learn more about the effects of playing football, the most watched sport in the US.
As Asplund and Best point out in their BMJ editorial, it's time to better understand those repetitive blows to the head that players endure. It's time for a long term study. If brain injury is avoidable, we should know how to make that happen. And if it's inevitable, players deserve to know that too.