Mako Vunipola says England coach Eddie Jones warned him "not eat too much" ahead of the autumn Tests starting in November.
England coach Eddie Jones will name his 45-man Elite Player Squad squad ahead of the autumn Tests at 10:00 BST on Friday.
Number eight Billy Vunipola says England are a more close-knit unit since Eddie Jones took over as head coach.
Wasps flanker Sam Jones is one of seven uncapped players in Eddie Jones' 37-man England training squad ahead of the autumn Tests.
Danny Care and Mako Vunipola will start for England as they chase a Grand Slam against France in Paris on Saturday.