Sure, she dresses celebrities so famous they need only one name (Demi, Keira, Mischa), but Rachel Zoe says that Hollywood isn't the only world she inhabits. "I kind of walk around in 'Rachel-world' most of the time," says the stylist, 36, whose fashion-advice book, Style A to Zoe, hits stores Oct. 3. "My brain is always moving fast. I've almost been hit by cars so many times because I sashay across the street, or someone will say, 'Did you see David Beckham in the elevator?' and I'm like, 'No!' I'm a little oblivious sometimes."

Still, even Zoe couldn't remain oblivious to the controversy that has swirled around her rise to fame. First there were the whispers when clients like Lindsay Lohan and Nicole Richie seemed to shed pounds once they came under her tutelage. Then in November 2006, soon after Zoe and Richie parted ways, reports surfaced that Richie had posted a blistering blind-item attack on her MySpace page insinuating that Zoe had an eating disorder; and Internet bloggers began alleging that Zoe encouraged clients to take diet and other drugs to lose weight. "It was being said that I was single-handedly bringing anorexia back!" recalls an indignant Zoe. "They were saying, 'Oh, my God—she's dealing crystal meth,' or, 'She's buying Mexican diet pills.'"

Zoe—who attributes her own super-slim physique to her "extremely high-stress life" and insists, "I've never done a drug, ever"—admits that "when this first came through I started laughing because it's so opposite of who I am! But all of a sudden it became this whole thing." And while she was concerned about the impact such talk might have on her career, Zoe says she was more worried about young fashion followers. "It's a very serious thing when [stars] are too thin," she says. "But to say that I did it? People are way overestimating my power."

Celeb fans also came to her defense and continue to rely on her red carpet expertise (see box). "Designers trust her, she's extremely professional and has a very strong team," says Demi Moore. "It's a perfect recipe for what you really want, which is to feel good when you walk out the door."

And yet even for a pro like Zoe, who lives in L.A. with her entrepreneur husband, Rodger Berman, 39, achieving that feeling isn't always easy. "You're almost always down to two choices: One more edgy and fashion-forward, and one more safe and simple," she explains. "That's the No. 1 struggle I have with my career. That and lack of sleep!"