Even being too skinny is a problem for some directors, including Michael Bay. According to Fox News, Megan Fox was asked to put on 10 pounds in three weeks to reprise her role as Mikaela in Transformers: Revenge of the Fallen. She had dropped the pounds while shooting her new film, "Jennifer's Body".

"I should have toned up for Transformers but I'm really lazy. I had to put on weight," she said. "I'd lost a lot of weight and got really scrawny, but I was told I had to put on size for Transformers because Michael (Bay, the director) doesn't like skinny girls."

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How did she drop the pounds in the first place?

"I just stopped eating," she said. "I don't eat very healthy anyway - I have a serious sugar tooth, so now I eat red-velvet cake before I go to bed every night, and if you eat meals later, you'll put on weight faster, so I had dinner at 10 p.m."

While she wouldn't reveal much about the film itself, she did reveal that the romance will be tamer than the last film.

"There are no big love scenes," Fox said. "At this point Shi and I have been dating for two years so we're at the bickering stage, like an old married couple."

Transformers: Revenge of the Fallen is currently in production and set for a June 26, 2009 release date.