I took a huge risk ten months ago: I decided to tell an embarrassing and very personal story.

It involved a secret drug problem, a nationally televised panic attack, and then my embrace of a life-changing habit that I had always thought was ridiculous.

As I made the rounds promoting a book I wrote on shows such as ABC's “The View” and Comedy Central's “The Colbert Report,” I may have looked reasonably calm, but underneath I was pretty scared. I worried these revelations could ruin my career.

But as it turned out, everything was fine. In fact, people were actually reading my book, and I was hearing from thousands of them. I realized all sorts of people were dealing with the same underlying issue that I had been battling for years: the voice in the head.

Watch the full story on ABC News' "Nightline" TONIGHT at 12:35 a.m. ET.

I’m talking about the incessant inner narrator we all have. It’s the voice that chases you out of bed in the morning and yammers at you all day long. It frequently has us judging other people and being ruthlessly self-critical.

For me, the voice in my head was largely about ambition. As a young reporter, I volunteered to go to war zones without really considering the psychological consequences.

When I came home, I got depressed and blindly, mindlessly self-medicated with recreational drugs, including cocaine and ecstasy. It was a monumentally stupid decision that ultimately led to the most embarrassing moment of my life when I was filling in on “Good Morning America” back in 2004. Just a few seconds into my spiel, I had a panic attack live on national television.

As I later learned from my doctor, the drugs I was taking in my personal life raised the level of adrenaline in my brain and almost certainly primed me to have that panic attack. It was this incident that helped me realize I needed to find a new way to deal with my inner narrator, and after a long, strange journey, I finally found something that actually works for me: meditation.

But meditation was something I’d always considered flaky. And a lot of my readers were similarly skeptical. Despite that, I eventually learned that meditation is simple, secular and scientifically validated. Studies show it can lower your blood pressure, boost your immune system and effectively rewire key parts of your brain. Many highly functioning executives, professional athletes and even U.S. Marines are now using meditation to be more focuses and less yanked around by their emotions.

Take Chris Nee, the creator of the hit kid’s show “Doc McStuffins.” She says her new meditation habit helps her better handle the hyper-critical world of Hollywood.

“I was in a place where I was ready to fight every single little point on the show. ... I think it’s very mentally exhausting to be in that place,” Nee said. Meditation "allows me to take a moment when negative responses come in and not take it so personally.”

And there’s Jason Hammel, one-half of the indie rock band Mates of State, who found that by meditating he’s actually honed his creative edge.

“When I started meditating, I was afraid. I thought that it would sort of breeze over all the passion,” Hammel said. “It’s the opposite. It’ll actually allow you to create better and express what you’re thinking more because you’ll focus on that one feeling or thought.”

Najme Alice, who graduated last spring with a degree in nursing, said she was consumed by anxiety about her future. The day after I met her, she had a job interview and said meditation helped her prepare.

Meditation allowed Alice to “hit the play button,” she said. “Now this is the time for me to start living.”

Father of two and recovering addict Chris Eckstedt said last summer he couldn’t see a future at all. It was a crisis brought on by his particularly dark inner narrator, which had been making him feel isolated and alone for years.

“When I was high or drunk, I all of a sudden felt like I fit in,” Eckstedt said. “I could have killed myself, and I would have missed out on so much. Who knows what the future will bring? I’m good right now. I'm so grateful for this idea of meditation.”

In my case, meditation helped me cut back on mindless behavior, like losing my temper, checking my email in the middle of conversations or eating when I’m not hungry.

Now, it didn't make my life a nonstop parade of rainbows and unicorns, which is why I came up with a somewhat tongue-in-cheek titled for my book, “10% Happier.”

But as I've learned after hearing personal stories from my readers, meditation can provide a happiness boost that goes well beyond 10 percent.

Watch the full story on ABC News' "Nightline" TONIGHT at 12:35 a.m. ET.