Washington (CNN) - The lifelong neurological maladies that some football players face have led President Barack Obama - a longtime Chicago Bears fan - to question whether the risks are worth it for college players.
In an interview released online Sunday, Obama said if he had a son, he'd "have to think long and hard before I let him play football."
College players are especially vulnerable, Obama told The New Republic, since they aren't represented by unions or heavily compensated.
"You read some of these stories about college players who undergo some of these same problems with concussions and so forth and then have nothing to fall back on," he said. "That's something that I'd like to see the NCAA think about."
In September, a study published in the journal Neurology suggested professional football players are three times more likely to have neurodegenerative diseases than the general population.
When researchers specifically looked at Alzheimer's disease and ALS - amyotrophic lateral sclerosis, also known as Lou Gehrig's disease - that risk increased to four times that of the general population.
The National Institute for Occupational Safety and Health, a division of the Centers for Disease Control and Prevention, had been following this group of players since the early '90s, when the NFL asked the institute to evaluate them for their risk of cardiovascular disease.
Other studies have linked repeated concussions in football players to chronic traumatic encephelopathy, a neurodegenerative disease with Alzheimer's-like symptoms. Those symptoms can include depression, memory loss and mood swings. Former Chicago Bears safety David Duerson, who committed suicide, was diagnosed with CTE postmortem. It can be diagnosed only after death.
In February, Obama told Bill Simmons of Grantland.com, a sports and pop culture news website, that he knew Duerson and "used to see him at the gym sometimes."
"Now, the problem is, if you talk to NFL players, they're going to tell you, 'That that's the risk I take; this is the game I play.' And I don't know whether you can make football (be) football if there's not some pretty significant risk factors," Obama said in that February interview.
In Sunday's remarks, Obama's tone seemed to shift. He conceded that "those of us who love the sport are going to have to wrestle with the fact that it will probably change gradually to try to reduce some of the violence."
– CNN's Nadia Kounang contributed to this report.