For years, John Hatty??? was a senior businessman travelling the world. The former scientist's job with a mining company took him to many fine restaurants where he would consume what he now calls his "three enemies" - sugar, salt and fat.    
But this all came to a halt when the 63-year-old discovered he had non-alcoholic fatty liver disease - a lesser known complication of obesity that now affects about one in three Australians. 
About 18 months ago, Mr Hatty, a father of four, was told the disease was causing catastrophic damage to his liver - an essential organ that breaks down food, removes toxins and regulates our metabolism.
While the disease does not produce symptoms for 90 to 95 per cent of people, it was causing fluid to build up in his abdomen. It was also triggering frightening lapses of consciousness, including one that put him in intensive care for three days.
"My specialist said you have two choices. If you don't get a liver transplant, you have two bad years ahead of you. And if you do get a liver transplant, there's every chance you will get two good decades," he said.   
This year, Mr Hatty became one of a growing number of Australians to receive a liver transplant for the condition which kills about 2500 people a year.
Liver specialists say that with two thirds of Australians now overweight, the condition is exploding. And while it once affected mostly older men, it can now be found in people in their 20s.
Associate Professor Paul Gow, a senior liver specialist at the Austin Hospital, said although some people of a healthy weight suffered from fatty liver disease, suggesting a genetic factor, most people with it are obese.
John Hatty is losing weight after he received a liver transplant for non-alcoholic fatty liver disease. Photo: Penny Stephens
He said mounting research suggested it may be caused by fructose (a sweetener found in many processed foods) and chemicals known as "advanced glycation end products" (AGEs), which are produced when foods high in protein and fat are fried.
"We're having more pre-prepared foods which tend to have more AGEs in them and it's making our livers sick," he said.
Associate Professor Gow said about 5-10 per cent of people experience potentially fatal consequences of it, including cirrhosis, cancer and liver failure. The trouble is, by the time you have these problems, it's usually too late. The only treatment is a transplant, and you may not qualify for the procedure or receive a donation in time. The disease can be diagnosed by a blood test which sometimes leads to an ultrasound and biopsy."
Dr Anthony Rode, a liver specialist at Epworth, said while fatty liver disease is potentially curable with weight loss, only about 20 per cent of his patients lost weight and kept it off. This is despite his clinic including dieticians, psychologists and bariatric surgeons to help people. With no signs of the obesity epidemic slowing, he is worried about how many people would suffer from it in the future.
"This is going to overwhelm the health system," he said. "It's huge."
As Mr Hatty continues to lose weight after his transplant, he hopes his story will raise awareness of the disease and encourage people to become organ donors.
"There's a big scar on my body that looks like an L for love," he said. "I'm so grateful."