The champion of Channel 5's first regular series last year also criticised the lack of aftercare that was available to housemates after the show finished, and said that he "fears" for this year's crop of hopefuls.
"I genuinely fear for them, they don't realise what they're letting themselves in for," he told The Wright Stuff.
"They give you very little preparation for what's likely to happen. From my year, with the 15 of us, I know that four of them have tried to commit suicide after the show just because of the ramifications and impact that it has on your life.
"You're not prepared and you don't have the aftercare that perhaps you should be getting afterwards. The people that are going in tomorrow, they're not gonna hear this."
However, he did not mention which housemates he was referring to while speaking on the Channel 5 talk show.
Allard-Morgan also spoke about his relationship with fellow housemate Faye Palmer, saying that they are still together.
"Big Brother is a game show, and everybody who goes in there plays a game, including myself. You come out and you're not sure if the person who you could have this relationship with was playing a game with yourself.
"And I knew that I was very much in love with her and it turned out she was the same so it worked out brilliantly."
Speaking about a possible TV show spin-off featuring the pair, he added: "We were looking into it, we filmed a pilot. It was great fun to do, but we're not sure what's happening with that at the moment, so we'll see."
Big Brother's latest series premieres tomorrow night (June 5), starting with an auditions special at 8pm, followed by the live launch at 9pm on Channel 5.
