Heading might not exist in football in 10 to 15 years time because of the risks involved, former Tottenham and Hull midfielder Ryan Mason says.
Mason, capped once by England, had to retire from football after fracturing his skull playing for Hull in 2017.
A recent study showed that footballers are three and a half times more likely to suffer from dementia.
“It wouldn’t surprise me in 10 to 15 years if heading wasn’t involved in the game,” Mason, 29, told BBC Sport.
“The research and the momentum it’s getting, I think it’s probably going to open up a lot more stuff that becomes quite shocking.
“I’m not sure footballers are fully aware of the potential damage. This is where the more research, the more understanding, the more education current players get, the better.
“It might even get to a point where you might need to sign something to say that I’m OK [playing with the risk].
“It really is concerning. The problem we have is you don’t know the effects until you get later on in life.”