Foden concedes he had issues off the pitch last season, which he has managed to solve.
"How strong he is for admitting it," Guardiola said. "A figure like Phil can be open minded and speak to all of society. Today the young teenagers and even older people struggle with that - nobody is away from that, everyone can be that.
"To accept the reality, wow. That’s why when I see him now - and forget about the level he is performing, which is a top level... it's about how he has been.
"The joy in the training session is back, his laugh and his voice in the locker room. That is enough. It’s just what we want."
Guardiola also said: "We’re always there for Phil.
"The club for that is beyond exceptional. I’m happy step by step he’s getting better. We always let them feel we are there, unconditionally whatever happens, I don’t care your performance when you feel that way, the human being comes first in front of everything in life.
"We try to take care of the people in that way. Everybody knows the level he played last season and the level this season is another situation. Phil feels good."