Appearing on Lorraine, Peter, who starred on the third series of the ITV show, said hunger is a real problem.
"I wish I'd known really how hungry you do get. I don't think you can prepare yourself, so maybe knowing wouldn't make a difference," he said. "Try and cut down the food before you go in so you don't feel the hunger too much. It's pretty hardcore."
Peter also revealed that his campmate Johnny Rotten, aka John Lydon, didn't have a toothbrush. Yes, really!
"The two weeks or so that he was in without brushing your teeth was pretty hardcore," Peter said. "Sorry Johnny, I would have bought you one had I known."
Guys, take note!
Peter, who currently stars on Strictly Come Dancing, also said "a lot of the cameras are hidden", but told the new set of celebrity campers to enjoy this once in a lifetime experience.
ITV have confirmed the full line-up of the 10 celebrities entering the jungle this year will be: Tony Hadley, Yvette Fielding, Chris Eubank, Jorgie Porter, George Shelley, Kieron Dyer, Lady Colin Campbell, Duncan Bannatyne, Brian Friedman and Susannah Constantine.
Two more celebrities are also expected to make a late arrival in camp.
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