To say Greg Smith was a gifted child is putting it lightly. He sailed through most of elementary school in a single year. By the age of 7 he was walking the halls of high school. At 10 years old he enrolled in college where he studied advanced level physics, French and calculus.

Today, Smith is 26 years old. Though it didn't feel like it at the time, he tells "Oprah: Where Are They Now?" that attending college at such a young age required him to grow up quickly. "It was a bit strange of course, being that much younger," Smith admits.

Via OWN

Though the other students were nearly twice his age, Smith says he wasn't ostracized. "I had lots of friends in college and hung out with a lot of the people there in my programs," he says.

"I had lots of friends my own age too, and I think that was really important," he adds. "I mean, sure we were in different grades, but we still liked a lot of the same things. We liked sports, we liked going out, just having a good time."

Though some parts of his childhood were normal, other kids his age certainly weren't being interviewed on "60 Minutes," "Late Show with David Letterman" and "The Oprah Show." Known as the "boy genius," Smith caused a media frenzy in the late '90s. “There would be people that would recognize me everywhere,” he recalls.

When his interview on "The Oprah Show" aired (and every time it re-ran) Smith says the servers at his school would crash because his email address was mentioned in the episode. "They just couldn't handle the constant bombardment of people who were interested in my story," he says. "And it was amazing, it was flattering, it was incredible to be a part of that."

The attention also gave the young man a platform to speak about the issues he's most passionate about. "It gave me a voice," Smith says. "And that was incredible." He went on to be nominated for the Nobel Peace Prize five times for his charity work campaigning for children's rights and safety.

As for his career, Smith is now a postdoctoral researcher at Mount Sinai where he studies stochastic gene expression. Simply put, he says his goal is to "build better drugs."

"So in your lifetime, will we cure cancer?" Oprah asks.

"That's a tough question to answer," Smith responds. "I think it's certainly possible in my lifetime that we'll be able to develop really effective, targeted treatments for people's individual versions of cancer that they have. And that is incredible."