Los Angeles: Hollywood superstar Will Smith has admitted he had no idea of the risks of brain injury his son might have suffered from playing American football.
Smith plays a neuropathologist who made the first discovery of a football-related brain trauma in his new film Concussion.
He said he felt a responsibility to inform parents of the hazards because he was not aware of the risks to his own son Jaden.
The actor, who takes on the role of the real-life Nigerian-born doctor who was the first to publish findings of chronic traumatic encephalopathy in American football players.
"I love football, I'm a football dad, I grew up with the Philadelphia Eagles and there is nothing better than that Sunday afternoon, so when I met Dr Bennet Omalu and I had him walk me through the science it became almost a burden.
I felt like I had to deliver the information because I'm a football dad and I did not know, I did not know when I watched my son play football in high school for those four years, I did not know there was a potential long term neurological issue.