So when the handsome author and TV host, 50, received the potentially devastating diagnosis that he had an adenomatous polyp, a precancerous growth in his colon that will require him to undergo frequent screenings for colon cancer, he turned to his friend for words of encouragement.
"I talked to Oprah about this right after the colonoscopy results came back," Oz tells PEOPLE. "Her main question, classic Oprah, was, 'I don't care about this stuff. Are you okay? That's the bigger question.' It's all about how do you deal with the rough waters you hit?" he says. "This was a storm that came over the horizon."
Winfrey, 56, was also inspired to make her own health a priority. "She said, this makes me want to get a colonoscopy right away," Oz recalls. "She'd been putting it off, like I would have done. But she saw how important it is to have early detection.”
He also says his mentor further inspired him to share his story in the hopes of encouraging more people to undergo colonoscopy screenings after age 50.
"Talking to people and giving them knowledge but not the visceral awareness doesn't work," he says. "Oprah taught me that. Use my story. The only way it's compelling is because you know me."