Former Big Brother star Chanelle, 28, wowed the Loose Women panel yesterday when she proudly displayed her size 16 body in a hot pink bikini while being interviewed.
She explained how she'd been "miserable" on previous diets while trying to keep her weight down, and now has a more relaxed approach to her eating habits.
"I was so miserable, all I wanted was a burger. I was always in a bad mood," she said. "I am a lot happier now, I have a healthier approach to eating. I can have a coffee and cake at soft play with other mums and not feel guilty. I used to take a Tuppaware box with grilled chicken."
But her former partner Jack has now hit out, saying he doesn't believe her.
Jack, 28, tweeted: "Why do i keep seeing things about Chanelle Hayes being HAPPY at 30 stone. Surely people don't believe this."
When one Twitter user replied to say Jack should be "ashamed" of tweeting that, Chanelle is not 30-stone, and she's too good for him, he replied: "Yer looks like it ..... Anything for pound note that girl."
He also alleged: "She put on weight and went on holiday for 4 hours to do pap shots for media attention .. she's not happy that weight #dvd."
Jack also alleged Chanelle used to be upset when she gained weight, and claimed she'd been messaging him recently, which is why he knew she was "unhappy." He did, though, admit he was probably wrong to have said 30-stone.
Chanelle has not responded to Jack on Twitter.
We've contacted her rep for comment.
Chanelle, however, has said frequently she's happy with her appearance. Speaking on ITV's This Morning in April, she said: "I don't think I look hideous, I think I look nice.. To be honest, I'm fine with the way I am, I'm really happy."
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