An Australian fitness instructor, who gained more than seven stones in four months as part of an experiment, says he is now hooked on junk food, reported Sky News. Paul “PJ” James, 32, a former model, went on his binge-eating escapade so he could understand his fat gym clients better. To gain weight, he ate kebabs and fry-ups, as well as bacon, chips and chocolate milk and went from 12.5 stones in January to his present weight of 20 stones. PJ gave up exercise and now feels physically terrible. “I feel down. I don't feel like doing anything. I used to eat lean meat and veg, now I've got a taste for biscuits and fizzy drinks,” he admitted. The former underwear model, who has strutted his stuff on the catwalks of Milan and Tokyo, said he had tried to do the experiment as carefully as possible, having regular blood pressure and health checks. Despite the checks there are still potential risks such as liver disease or heart problems, health experts say. PJ aims to begin a diet in July and, together with his extra-plump clients, be lean and mean by Christmas.