The TV personality underwent gastric sleeve surgery in 2017.
Speaking to a local publication, she shared, "I'm the worst dieter!"
"I've never not eaten when I've wanted to."
The surgery means she has a signed doctor's certificate making her "exempt" from eating certain foods - on medical grounds.
Yvie, 48, and best friend Angie Kent, 28, were the first confirmed stars for the new season of I'm A Celebrity.
Speculation is rife that they'll be joined by former Bachelor Richie Strahan.
The season premieres on January 13.