Jessica Simpson Dishes on Her Elle Cover Shoot: I Ate Cheesecake!

Most celebs would exercise like crazy and crash diet before a big magazine photo shoot, but not pregnant Jessica Simpson — she gladly gave in to her sweet tooth prior to posing nude for the cover of Elle. "I ate cheesecake before we shot," the 170-pound fashion mogul proudly boasts to USA Today. And although baring it all for millions to see would typically make the bashful Simpson, 31, turn red, she says she "wasn't nervous at all" for this special photo shoot, which was witnessed by only the photographer, her fiance Eric Johnson, her publicist, and a couple of her best friends. "Normally, I'm so shy," she notes. "I'm not the person you see photographed in a bikini on a beach. For some reason, being pregnant, it's so easy for me. I feel so comfortable in my skin … It's just really a celebratory moment for me. I'm glad people are reacting positively [to the cover]."

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And it's a moment she's relishing as she anxiously awaits meeting her daughter for the first time. Simpson says she's not afraid at all — even though her doctor tells her Baby Girl Johnson will likely weigh in at a whopping 10 pounds. "I figure if all these women all around the world can do it, I can do it," she says. "[The baby] is in the 90th percentile of weight right now, so she's a big un. She's going to be a very big baby, but I guess that's what I get for letting a baller knock me up," jokes Simpson.

[Related: omg! Interviews Pregnant Jessica Simpson: 'I'm More Confident Than I've Ever Been']

When she does give birth, she will have a lot of helping hands at home, including her sister Ashlee's 3-year-old son, Bronx Mowgli. Not only does the blond cutie (dad is former Fall Out Boy bassist Pete Wentz) chat with his little unborn cousin all time, he's already set aside his old toys for her. "It really makes your heart melt," gushes Simpson. "Yesterday, he said he was going to teach her how to crawl and then how to walk. 'OK, you can do that, Bronx.' It's so cute."

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