Superstar and longtime Atlanta resident Elton John said he was the "luckiest person in the world" not to have contracted the HIV virus that causes AIDS while the epidemic was killing many of his friends in the 1980s.

In a revealing interview Tuesday with NBC's Matt Lauer, the singer and songwriter acknowledged he regularly practiced unprotected gay sex at the time and that he didn't have a fear of contracting the disease because he was often high on drugs and alcohol.

"You know what, when you take a drug and you take a drink and you mix those two together, you think you're invincible," he told Lauer on The Today Show, adding that he often couldn't remember what he'd done the night before.

"I came out of this HIV-negative," John said. "I was the luckiest person in the world."

He also said he "wasted such a big part of my life" when the epidemic first hit because he was so self-absorbed with his addictions and didn't use his rock stardom to help fight the disease.

"You know, I was having people die right, left and center around me, friends," John said. "And yet, I didn't stop the life that I had, which is the terrible thing about addiction. It's that — you know, it's that bad of a disease."

Today, however, the six-time Grammy award winner, who has sold more than 250 million records, says he is committed to fighting AIDS, the stigma associated with the disease and discrimination against homosexuality. He's able to do so because of what he calls his biggest achievement: getting sober.

The 65-year-old singer was on The Today Show promoting his memoir, "Love Is The Cure: On Life, Loss and the End of AIDS," which was released Tuesday.

"I'm making up for it," he said of his inaction in the fight against AIDS in the early years. "There's so much more to be done." His Elton John AIDS Foundation has raised more than $275 million in the fight against the disease.

John also revealed that he never publicly said he was gay until 1976 because no one had ever asked him, although he said he was living an openly gay lifestyle. He said Rolling Stone reporter Cliff Jahr broached the subject in an interview.

"I said, 'I've been waitin' for people to ask me this. It's not exactly a secret. I live with my manager. I'm openly gay outside. I don't have a girlfriend. And nobody's ever actually out — I just thought it was common knowledge.'"

John entered into a civil partnership with his longtime partner, David Furnish, when it became legal in Britain in 2005.