Karras died Wednesday at his home in Los Angeles. It was announced earlier in the week that Karras was suffering kidney failure. Previously, family representatives said Karras had stomach cancer, heart disease and dementia.
Karras was a defensive lineman who played at the University of Iowa, where he won the Outland Trophy as the best interior lineman in college football in 1957. He was inducted into the College Football Hall of Fame in 1991.
He was the 10th overall selection by the Detroit Lions in the 1958 NFL draft and played 161 games in a career that spanned 1958-70. Karras was selected to the Pro Bowl four times -- 1959-61 and 1965 -- and was named to the NFL's All-Decade Team for the 1960s.
Even before his playing career was over Karras was noted for his acting. He played himself in the movie version of "Paper Lion" and had a series of smaller TV roles before being cast as "Mongo" in Mel Brooks' Western spoof "Blazing Saddles."
His biggest role in television was as George Papadopoulos, who adopted the title character "Webster." That series ran for four seasons.
Karras starred opposite his real-life wife Susan Clark in "Webster." Clark is among Karras' survivors.
Karras in April joined the lawsuit filed by former players against the NFL related to head injures leading to health problems, including neurological conditions.