And why is that?
"Because I feel like sweatpants we should be in all the time," she said before the BCBG Max Azria show, wearing a belted BCBG dress, Max Azria high heels and a gold Tiffany key. "So I would like to design amazing, sexy sweatpants that you wear with heels."
That unusual style was worn by Mariah Carey and Janet Jackson last year, but may not appeal to everybody. But the 31-year-old explained how BCBG is far more versatile: "I just love that it's really comfortable, I love that it's really glamorous, I love that you can dress it up or dress it down. I'm a big fan."
Not that Hewitt doesn't have fashion regrets.
She recalled a 2000 fashion and hair misstep: "I wore nude, suede pants and a corset that was shorter so it had my stomach showing [see the pictures here!], to "The Beach" premiere. Why I did that, I have no idea. And I crimped my hair with it, on top of it. It was absolutely horrible. I'm surprised they didn't kick me out of the business."
But Hewitt was permitted to continue in Hollywood and now admires the style of a fellow actress. "I would love to accidentally get locked in J. Lo's closet for two days and then take pictures of myself in all the amazing clothes," she laughs.