'Shadow' of his former self: Meet the man who lost 550 pounds

Need inspiration to put down the fork and start moving? Consider the remarkable story of Justin Willoughby, who dropped nearly 600 pounds over a decade through sheer determination without the help of weight-loss drugs or surgery.

As a teen, Willoughby suffered from stress and severe anxiety and turned to food for comfort. He kept eating and felt addicted to food. His weight climbed to a terrifying 799 pounds when he was just 16, and the 5-foot-8-inch Willoughby feared for his life.

“There were so many emotions going on in my head: fear, anxiety, am I going to live or am I going to die?” Willoughby, now 27, told Savannah Guthrie on TODAY Friday. “So all those things were just rushing through me.”

His doctors didn’t know what to do. “Their hands were in the air,” Willoughby said.

“I mean, what do you do?” he said. “You have a 16-year-old who weighs 799 pounds.”

He relied on his faith, and began his first workout, a painful, single first step.

“I had a belief in God," he said. "That was a significant part."

“There were so many emotions going on in my head: fear, anxiety, am I going to live or am I going to die?," says Justin Willoughby, 27.Today

He started eating smaller meals and made healthier food choices. He began exercising, though it wasn’t easy.

“My first exercise was just standing up and sitting back down,” Willoughby said. “That was very painful. My back started hurting, my legs started hurting. That was a workout for me.”

WATCH: How these people lose over 294 pounds

But it was enough to keep him going, and he adopted the motto One Step.

He continued exercising, and now works out about 90 minutes a day, eventually reaching a low weight of 207, according to the Huffington Post. Through weight lifting and increased muscle mass, he now weighs 235.

Willoughby now works out 90 minutes a day.Today

Guthrie congratulated him on his new body. “This is amazing,” she said. “You’re a shadow of your former self.”

Willoughby, who had skin-reduction surgery after his weight loss, hopes to inspire other people to lose weight and become fit, and is a motivational speaker, author and personal trainer, according to his Facebook page.

It’s a world away from his life as a boy, when he turned to food to manage his emotions.

“I was always a little bigger, bigger than my classmates,” he said on TODAY. “I was starting to get addicted to food. I loved food. If I could do anything, I’d marry food. I loved it that much. I began to get addicted to it and I went to it a lot.”

WATCH: Mom loses more than 158 pounds in 15 months

Lisa A. Flam is a news and lifestyles reporter in New York. Follow her on Twitter.