After leaving the jungle, Simons said: “I had a mini hypoglycaemic incident last night so for two days I have wondered why I was not right.
“I had low blood sugar levels and they took me out to the medic hut. They were great. I feel better.”
A hypoglycaemic incident can lead to symptoms including dizziness, feeling shaky, a pounding heartbeat, confusion, sweating, hunger, irritability and even loss of consciousness.
Simons was the fourth celebrity to exit the jungle, following Noel Edmonds, Malique Thompson-Dwyer and Said Khan out of the I’m A Celeb camp.
Although she told co-hosts Declan Donnelly and Holly Willoughby that she was “so happy to be out,” the actress also said her time on the show had “changed” her – by forcing her to face her deepest fears.
“I really am afraid of heights, but I did the cliff and the zip wire and abseiled,” she said, adding: “I had an incident in the water while filming a few years back and I’ve got this stupid phobia where I have to hold my nose. But doing a challenge where water is coming up is a massive deal for me.
“And I hate insects and I got covered in them, so I’m glad I got that in before I left. I feel like I could have done more trials, but glad I did the bugs one.”
Simons also admitted that it was “harder” than she ever thought it would be, explaining: “What killed me the most was the boredom. I am no good at sitting around.”
I’m A Celebrity… Get Me Out Of Here! continues on Wednesday at 9pm on ITV