In this photo provided by Subway, Jared Fogle signs a copy of his book, titled "Jared." Reuters

For 15 years, Jared Fogle was known for being the "everyman" spokesman for the Subway sandwich brand. As "the Subway guy" or just "Jared," Fogle made TV commercials and trips around the world showing off the pants he wore when he weighed 425 pounds -- that is, before he began eating a diet largely consisting of Subway sandwiches and eventually lost more than half his body weight.

His fame brought him a net worth of about $15 million and earned him a book deal, but his celebrity began to unravel after allegations came up in recent weeks about his ties to a child pornography investigation involving the former head of his charity, the Jared Foundation. The sandwich giant ended its relationship with Fogle Tuesday when news broke that he would plead guilty to child pornography charges Wednesday. In a matter of weeks, he went from being the face of healthy eating and an advertising icon to a tarnished figure embroiled in a child pornography scandal.

Before he was seen on Subway commercials, Fogle was a student at Indiana University in Bloomington, who found himself obese from a diet of mostly junk food, USA Today reported. He eventually started to lose sleep as the fat around his neck would obstruct his windpipe at night. After falling asleep behind the wheel and waking up in a ditch, Fogle decided to change his eating habits.

"My whole life was about planning ahead to avoid embarrassing situations," Fogle told USA Today.

That's when he walked into his first Subway, in 1998, and ordered his first sandwich. Within a year, he was down to 190 pounds.

After hearing about Fogle's massive weight loss, a friend wrote a story about him for Indiana University's student newspaper in 1999, the Los Angeles Times reported. Months later, Men's Health ran a story that included Fogle and his diet, which eventually caught the eye of Subway executives.

Subway decided to shoot a 30-second ad that zoned in on its menu's health benefits in 2000. About 300 commercials later, people still recognize Fogle as the face of the sandwich brand.

During his spokesman stint, Fogle traveled the world as Subway's real-life success story -- an average guy who shed the weight and kept it off. He's been the grand marshal of Nascar races, flipped coins at college bowl games and even made trips to Washington to lobby for healthy school snack options, CNN reported. Fogle also gave motivational speeches, receiving $5,000 to $10,000 per engagement.

The public's perception of Subway as a healthy alternative to fast-food giants like McDonald's or Burger King grew with Fogle's fame and changed the market. In recent years, McDonald's has added more health-conscious items to its menus.

"Jared gave Subway the health halo before any of us even knew the term," Robin Lee Allen, executive editor at the trade publication Nation's Restaurant News, told USA Today in a 2013 feature on Fogle.

Eventually, Fogle became the most recognized advertising brand in the food industry, Ad Age reported. It was Fogle's identity as an "everyman" that actually contributed to people relating to Subway and its brand, Ad Age said. Tony Pace, Subway's chief marketing officer, told the Daily News he could attribute much of Subway's growth in the past 15 years to Fogle.

In 2004, Fogle established his charity, the Jared Foundation, to combat childhood obesity, Heavy reported.

The FBI raided Fogle's Zionsville, Indiana, home last month. Just weeks before, Russell Taylor, the former executive director of The Jared Foundation, was charged with producing and possessing child pornography.

Subway said it believed the raid related to the child pornography investigation, and said the company and Fogle had mutually agreed to end their relationship. “We no longer have a relationship with Jared and have no further comment,” Subway wrote on its Twitter account, which is followed by 2.26 million people.

In court documents released Wednesday, federal prosecutors allege Fogle engaged in sexual acts with minors and received child pornography. He is expected to plead guilty to one count of travel to engage in illicit sexual conduct with a minor and one count of distribution and receipt of child pornography.

He will no longer be the face of healthy eating.