david smith 1david smith 2Three years ago, David Smith became the poster boy for the extreme slim-down.

The star of TLC's The 650-Pound Virgin, Smith dropped a jaw dropping 400 pounds, became a trainer, found his first ever girlfriend, and inspired millions to get fit. Yet three years later, he has regained nearly 300 pounds and is morbidly obese once again.

The reason for the setback? On his path from dud to stud, Smith only tackled half his problem.

Focusing on diet and exercise, "I looked really good on the outside but inside I was a terrible mess," he said on Today. "I saw someone who didn't know who they were. All my life I was this monster in my head. And all of the sudden, to be this good-looking guy just blew my mind away. I didn't know how to deal with it."

The pressure didn't help either. Suddenly a public figure, "A lot of people were counting on me to be inspiring. I didn't want to let anyone down. I just didn't know how to cope," he said.

It's a sad reminder that losing weight is not just about what is happening on the outside. Too often, we focus on that number on the scale, a taut tummy, and buff arms. But that almost always guarantees failure.

Like so many others, Smith was only focused on the physical. He never dealt with the emotional issues that caused him to overeat in the first place. It's why people commonly gain back most, if not more, of the weight they worked so hard to lose. And in cases of gastric bypass patients, where it's physically impossible to eat like they used to, they will often transfer that food addiction to something else, like shopping, gambling, or drugs.

Now fighting to be fit again, Smith is praying for a second chance. This time, however, he knows success is about much more than looks. "As much as you work on the outside, you have to work on the inside," he said. "If your foundation isn't built up, you are just going to crumble down."

See more of David's Today interview story here:

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