Brett Favre is calling for a ban on youth tackle football ... saying he believes no child should participate in live, full-contact games until at least the age of 14.
The Hall of Fame QB explained his stance to Harvey and Charles on "TMZ Live" ... saying he believes the ban could help prevent concussions and long-term brain issues.
"What I was told basically is the human head is completely developed by age 15 to 18," Favre said. "And I may be wrong or off a little bit, but that's what I remember.