Jessica Biel loved New Year's Eve diet

Jessica Biel relished the chance to play a pregnant woman in New Year's Eve - because she didn't have to watch her weight.

The actress plays an expectant mother in the upcoming romantic comedy and insists it was a relief not to have to obsess over her calorie intake on the shoot.

She tells U.K. talk show host Graham Norton, "It was so good! (I had a pregnant belly) suit on that went from here to here (across belly), I had the biggest boobs that hung to here, I ate whatever I wanted - it was great!"

The brunette beauty admits strict diets and gruelling gym sessions are her least favorite part of making movies, and reveals she loses her willpower when it comes to junk-food binges with friends.

She adds, "You spend months and months and months training with crazy martial arts instructors and you're on crazy diets. It's the hardest experience, it really is 'cause you're eating a lot of boring stuff - chicken breasts and vegetables all the time. But it's cakes and pastas and breads and sandwiches and croissants (you crave) all the time, that's all you can think about.

"(Then) you don't crack just slightly, you crack bad. I was with my girlfriends, we were out in New York City for a night, it was the cheat day. I saw Dunkin' Donuts. I said, 'Pull the car over, pull over right now!' We ran in, I got 24 donuts. We went to a pizza joint and we got two large pizzas. I sat in the car and I put as much bread and dough in my mouth as I could possibly manage. It was the best moment."