Lucy Mecklenburgh lost two stone while competing on "Bear Grylls: Celebrity Island".
The former "Only Way is Essex" star didn't realise she'd dropped so much weight until after she left the secret tropical location, but is relieved she had listened to producers before going on the gruelling show, which sees a group of stars dropped on an island and told to fend for themselves, and piled on the pounds in the run up to her stint.
She told the Mirror Online: "I was told you should get used to eating less and less but then the I was told: "No, no, no you need to put on some weight. So I put on half a stone.
"It was weird because when you're there you don't really feel as thin as you are because you don't have a mirror so you don't really know how tiny you are."
However, the 26-year-old beauty had no issues putting the pounds back on as she "ate a lot" and managed to get back up to her starting weight within just three weeks.
Taking to her Instagram account, Lucy uploaded a photograph of her body after the show and then three weeks on and accompanied it with the caption: "My poor little body!!!! Soooooo emotional watching the last ep of #celebrityisland .. I can't believe we did it.. I can't believe I did it what an experience! I will never doubt myself ever again!! Met some incredible people that will be friends for life. So proud of us all!! #celebrityisland #beargrylls #theisland PS It only took me 3 weeks to put all my weight back on! I ate ALOT HAHAHHA!!!! (sic)."
Despite feeling hungry and grouchy while on the island, Lucy had her now-boyfriend Ryan Thomas to keep her in the right frame of mind and the pair got on so well during the challenge that they decided to give their relationship a go when they left the island.
Ryan, 33, said recently: "It was amazing to have Lucy there with me.
"We are of a similar age and she was a companion. It's nice having someone to look out for you. It was a real pleasure to have her there for me."