The “world’s fattest man,” or former fattest man Paul Mason, lost an astonishing 650 pounds and is now on a quest for the United Kingdom's healthcare system to fund his skin removal surgery.

Mason, 51, celebrated his weight loss with before and after photos on Thursday, thanks to the help of the UK’s National Health Service. According to the Sun, the NHS funded gastric bypass for Mason, leading to the his weight loss. Mason, an ex-postman from Suffolk, lost about two-thirds of his 1,000 pound weight. Now, at 330 pounds, the NHS said his stomach was reduced to the size of an egg.

Before the weight loss, the half-ton Mason used to consume up to 20,000 calories a day, solely eating takeout food, fried foods and potato chips and getting around on an electric wheelchair, the article said.

Mason said his eating habits stemmed from childhood bullying, which led to a compulsive eating disorder that only became worse when his father died in 1986. Once, Mason said, firefighters even had to remove the front wall of his home and lift him with a forklift in order to take the then 800-pound man to the hospital for a hernia operation in 2002.

Nowadays, the 330-pound Mason said that he dines on vegetables and small portions.

Meanwhile, Mason said that he's not finish shedding the pounds. He wants to continue losing weight to get down to 200 pounds.

“I still have a way to go,” Mason told the Sun. He also added that he wants to claim the title of “world’s greatest slimmer,” a shift from his previous title of “world’s fattest man.”

“I was ashamed to be called the fattest man in the world because I knew I’d got myself in a hell of a state,” Mason said. “I am proud that I have shown to other people with weight problems what can be achieved.”

Mason also wants to undergo further surgery to remove the folds of skin and loose tissue left after he lost some weight. According to the Sun, Mason is fighting with the NHS to fund his skin removal surgery, which can cost up to $50,000. Many Brits, however, have an issue with the NHS providing more surgery funding for Mason, as his medical bills reportedly have cost taxpayers more than $1.6 million so far, the newspaper reported.

Mason, who now uses a wheelchair because he said his loose skin inhibits his walking ability, is dead set on making it happen.

“The NHS says my weight must be stable for two years before they will consider operating on me to remove the loose skin,” Mason said. “But I want the surgery as soon as possible as it will enable me to become more mobile — and that will help me keep the weight off.”

“Once I get rid of the spare skin I also hope to be able to go swimming and cycling and join a gym — and find a girlfriend,” he said.