Jessica Biel's Diet Drives Her "Nutso"

Jessica Biel is famous for her rock-hard body but the A-Team hottie says it doesn't come easy — it involves constant exercise and a diet she describes as "the worst."

Jess works out two or three days a week with a personal trainer, but the actress fits in exercise every day. "I used to do a lot of ballet — it’s the most amazing workout," Jessica tells the UK's Glamour magazine via Huffington Post.

She adds: "Every day I do something, whether it’s in the gym, the pool or hiking with my three dogs."

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What about her diet? Justin Timberlake's girlfriend won't touch bread, dairy, sugar, salt or much meat when she is working. "Oh, it's the worst!" she says.

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But she allows herself time out from such unrelenting discipline: "When I'm working and I eat healthily all week, I then give myself one day — usually Sunday — when I just eat what I want. You have to, otherwise your mind goes a little nutso," she says.