I played organized football from 3rd grade through high school. Played OL and then moved up to TE/DE in later days. My senior year I was the gunner on punt returns (ran back up the wall to block oncoming players). I do not have any problems at age 60. I do have bad knees, but I attribute that to basketball and all the jumping drills/rebound drills from 5th through high school.
I allowed all my sons to play if they wanted (2 did/ 2 did not). Older son has no injuries, Offensive line. Youngest had a concussion, but doesnt' have any lasting injuries - now 20.
The older son does have back problems and has to go to doctor often. But, that is due to being hit from behind at stoplight twice. Both times he was at a dead stop waiting for light to change. But, he still drives and stops at stop lights waiting for them to change to green. Maybe I should talk to him and tell him that if he wants to have a fulfilling life past 25 (current age) that he should no longer commute in city traffic. It's just not worth the risk. This commuting has done more damage than 5 years of football.