Bednarik, 85, was listed in serious condition after he was admitted to St. Luke's Hospital in Bethlehem, Pa. last week with shortness of breath.
"He was a little anemic and dehydrated," son-in-law Ken Safarowic, a spokesman for the Bednarik family, told the Daily News. "I don't think it was any one significant issue. A bunch of things just ganged up on him at the same time. The heart and organs weren't affected. He's in a good shape otherwise."
Safarowic said the family was overwhelmed by the amount of phone calls they've received from Bednarik's former teammates and the Hall of Fame.
"We've got to hang on to him for a while," Safarowic said. "There are not many guys from that era. Chuck has another game-saving tackle left in him."
The Associated Press contributed to this report.