Portia de Rossi: I Once Ate “300 Calories” a Day

 Jim Smeal/WireImage.com

Portia de Rossi still cuts a lean figure these days — but it's nothing compared how she appeared (and how little she ate) during her battle with an eating disorder. The actress, 37, gets seriously frank about it on Monday's Oprah Winfrey Show.

The star says that at the height of her struggle, she consumed just "300 calories…a day." de Rossi chronicles the scary period in her life in her new book, Unbearable Lightness.

Her lowest weight? 82 pounds, she tells Oprah Winfrey.

"It wasn't that I was proud of it," de Rossi clarifies. "But it was certainly a recognition for my self-control. I definitely had some pretty amazing willpower to get down to 82 pounds. And that's what I was holding onto to. I didn't think about anything else."

Her life is much happier these days with wife Ellen DeGeneres. De Rossi recently took DeGeneres' last name legally (she'll keep de Rossi professionally).

"I love her and I am very proud to be her wife," she explained of the name change. "I made up my name," adds the star, whose given name is Amanda Lee Rogers. "Because I thought it was important to be independent of my family and …be an individual…as I have gotten older, I've realized the importance of belonging, and I really wanted to be a part of Ellen's family…By taking her name, [it] makes me feel like I have a family."

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