A student has lost more than 17 stone in just nine months after starring in a Channel 4 show.
James Dunn, from Liverpool, said “ridiculous portions” of junk food and lack of exercise saw him reach 32 stone by his mid 20s.
The 28-year-old claimed he knew he had to act when he was unable to fit on an Alton Towers ride and when he was unable to keep up with his 12-month-old niece.
Dunn has spent the past year changing his diet, undergoing weight loss surgery and following a gruelling exercise regime.
His transformation was filmed for Channel 4’s Make My Body Better with Davina McCall.
Dunn said: “A couple of years ago a group of us went to Alton Towers, we were having a good time and we went to get on the first ride.
“I sat down and the bar wouldn’t fasten over me.
“A staff member tried but they couldn’t do it so another had to come over to help.
“There ended up being two people trying to fasten it over me and they still couldn’t do it so I had to get off in front of the crowd of people.”
Dunn, who’s completing his final year at Edge Hill University while working as a primary school teaching assistant, said that his studies and part time job meant that he would order a late night takeaway up to four times a week.
“It would always be late in the evening and they weren’t normal portions,” Dunn said.
“I’d sometimes order a pizza and a kebab and then have chips and a sugary drink.
“I might have ice-cream after it. It was always ridiculous portions.
“I’ve always known I had problems with weight, I was always bigger at school but I used humour.
“I thought, if I make the joke first then it doesn’t matter but it was always something that I struggled with.”
At his heaviest, Dunn said that his size became such a problem that it affected simple tasks like visiting a local park with young relatives.
“I’ve got two nieces and when one started walking we’d go out with them and I found that I couldn’t keep up,” he said.
“I thought, if she’s 12 or 18 months and I can’t keep up then something isn’t right - she’s a toddler.”
TV producers challenged Dunn to lose 17st in nine months in order to be fit enough to compete in a professional horse race for the show.
He was given gastric sleeve surgery to remove around three quarters of his stomach and was introduced to personal trainer Mark Grice.
The Liverpool-based fitness specialist placed Dunn on a strict training regime and helped him ditch the high fat diet.
Dunn has switched sugar and carbs for a high protein diet and now weighs 14st 4lbs.
“I don’t want to inspire anyone to go out and get weight loss surgery but when you get to 32st sometimes there aren’t many other options,” he said.
“The surgery might have bought me another 20 years, I could have been dead in 10.
“I tried every diet there is but I’d always done it in secret. If I wanted to give up there was no one to say ‘you can do it’ because I didn’t tell anyone.
“It’s doing it so publicly that has kept me going - I’m not just accountable to myself now. I’m accountable to my friends and family who spent years worrying about me, to my mum who thought I could die of a heart attack.”
Dunn said that shedding the pounds has changed his life dramatically and even his students have noticed.
“The kids at school noticed but they thought they were being cheeky asking if I’d lost weight,” he said.
“They’d say things like ‘have you had a haircut or got a new top?’
“My family are made up, I’ve only realised how much they worried about me until after I’d lost the weight.”
The 28-year-old now hopes to team up with his personal trainer to educate young people about healthy eating.
“I’d like to use my story to help other people,” he said.
“If something like that was in place when I was in school I might not have got to where I was.”
Channel 4’s Make My Body Better with Davina McCall is now available to view online.