Cameron Diaz was "literally debilitated" by fear a week before the release of her first book.
The 44-year-old actress made a name for herself as a writer when she released The Body Book: Feed, Move, Understand and Love Your Amazing Body in 2013.
And despite the tome being a resounding success, becoming a New York Times bestseller, Cameron has revealed she struggled with extreme levels of anxiety before it hit shelves.
"Right before the book came out, I was on my back for a week. My back went out. I couldn’t breathe,” she said, while speaking at Nicole Richie‘s Pearl xChange at The London in West Hollywood, California.
“I’ve never had that kind of thing where I was just literally debilitated. I realized I was just so scared that I was going to put this thing into the world and everybody’s going to see me, and what if they don’t like me? What if they think I’m crazy or I’m stupid? I was like, oh God, this is so painful."
Cameron has enjoyed huge success in Hollywood, starring in films including The Mask, There's Something About Mary and The Other Woman. But launching her career as an author was an entirely unknown prospect for the actress, who admits she was more than a little daunted.
"It was revealing about who I was. Movies are like totally fake. It’s not me at all. It is, but they’re characters. This book was all me. There was no hiding. I was so open and so raw," she explained.
She needn't have worried though, as fans flocked to buy the tome and inspired Cameron to work on her second literary offering - The Longevity Book: the Science of Aging, the Biology of Strength, and the Privilege of Time - released in June (16).
And while her writing career has proved financially and critically rewarding for her, Cameron added to the crowd that she measures success in a different way.
"Success is really not about what somebody else says. Being a New York Times bestseller, to me, that’s not the success of the book," she said. "The book isn’t the numbers that got sold. It was that I had an intention, and the intention was to get that information out to as many women as I could."