The 20-year-old has been in scintillating form for City this season, scoring four times in the first five Premier League games of the campaign to help them to the top of the table, and has now vowed to clean up his act off the pitch.
"I have to improve healthy eating a lot," the Brazilian told The Sun. "At home I don't feed myself so well. If I'm travelling, I eat bad things like pizza and pastries. I could eat pastries every day.
"I don't know if it's because of my age that it doesn't make any difference yet - but I'll still have to work.
"I will [have] to eat better now or my mother will tell me off."
Jesus, who joined from Palmeiras in August 2016, has 12 goals in 18 appearances for City to date.