A 31 year old man who was dangerously close to  death because of overeating  has shed nearly 30 stone - and started a new life as a fitness instructor.

David Smith was given months to live after he ballooned in weight to 45 stone by gorging on pizza, chocolate and burgers every day.

But he managed to slim down to 16 stone after a fitness instructor coached him through a gruelling two-year exercise regime.

The drastic weight loss left him with an unsightly flabby appearance though, and he had to have four operations to remove 30llbs of excess skin.

He also needed laser surgery on his eyes and dental work on his teeth, which had been destroyed by fizzy drinks.

Mr Smith, from Phoenix, Arizona, said: "I was given just four months to live when I was 26 because I was so overweight. I was a man mountain.

"I was written off by everyone, even myself, but all of a sudden I woke up from my despair and I realised feeling sorry about my life wasn't going to solve my problems.

"I decided to change my existence and started exercising. Now I'm a completely different person, not just physically but mentally too."

He told how his weight made him a target for bullies - who called him the "elephant man".

"I would have sticks and stones and dog mess thrown at me and I would be spat on," he said.

"I've had a broken arm and black eyes because people didn't like me because of my weight.

"It got so bad that I didn't want to leave the house and I didn't even feel comfortable in my own backyard until it was dark out."

But after meeting local radio DJ and fitness instructor Chris Powell, he started going to the gym and eating salads.

Now he hopes to inspire obese children and adults in Britain to change their lives.