Sigler, 21, visited The Early Show to discuss her new book, "Wise Girl: What I've Learned About Life, Love and Loss," that documents her problem and other obstacles she faced in life.
"I have something called exercise bulimia, which is where you rid of your calories by over exercising. I ended up starting at a routine which was, you know, 20 minutes in the morning and cutting back a little on my calories. And it snowballed into six or seven hours a day of exercise," said Sigler.
Sigler shot "The Sopranos" pilot, when she was at normal weight, the summer right before she started her junior year of high school. The series' first season, however, did not begin production until almost a year later.
In those intervening months, Sigler fell ill for the first time. Her ability to lose extreme amounts of weight was a revelation. "It was something you could have absolute full control over," Sigler said.
By the time Sigler arrived on the set to begin shooting the first season, she was already at the beginning of her recovery. But, to most cast members, she looked like a shadow of her former self.
"I remember [actor] Jim Gandolfini took my arm and wrapped his whole hand around it," Sigler said. "And he was like, 'Are you eating?'"
She told him she was fine.
"He could tell I didn't want to talk about it, so he left it alone," she said.
In the book, she reveals how the show's creator, David Chase even phoned her mother to ask about her health and she voices her concerns that she might be replaced.
Only during the second season did Sigler open up to her TV family. "It took me that whole year to come to terms," she said.
At that point, Sigler began speaking publicly about her illness on talk-shows and on-camera announcements.
When Gandolfini heard Sigler had gone public, he also reached out. Sigler recalled: "I remember, one day on the set, we were sitting on the couch and he said, 'You know, I think it's really great what you're doing, talking out about what you went through, because it's hard to put yourself out there to help other girls."
Fast Facts On Jamie-Lynn Sigler
- Sigler filmed her first major feature film this spring called "eXtreme Dating." The movie focuses on 20-something friends who decide the only way to win over one's true love is to bond through extreme circumstances.
- Sigler currently stars as Meadow Soprano in the critically acclaimed HBO original series, "The Sopranos." For her work on the show, she received the 1999 and 2000 Hollywood Reporter YoungStar Awards for Best Young Actress in a Dramatic TV Series and both 2001 and 2002 ALMA nominations.
- The fourth season of "The Sopranos" is set to air in the fall of 2002.
- Sigler will make her Broadway debut starring as Belle in Disney's "Beauty and the Beast" in October.
- Sigler started her acting career at age eight in New York regional theater. Since then she has performed in more than two dozen theatrical productions including "Annie," "The Wizard of Oz," "The Sound of Music," "The Wiz" and "The Diary of Anne Frank."
*In the summer of 2001, Sigler starred in a 15 city tour of the Rodger's and Hammerstein's musical "Cinderella," performing the lead role along with Eartha Kitt as her Fairy Godmother. Music has always been Sigler 's first love; performing in theater from a young age it was natural for her to return to her musical roots.
- Sigler is half-Cuban and half-Greek. She is from Jericho, Long Island, NY and currently lives in New York City. She recently purchased a home in Las Vegas.
- She is the spokesperson for the National Eating Disorders Association (NEDA).