Mar 4, 2011 21:51 GMT  ·  By

Recent photos of “Mad Men” actress January Jones show her that she’s lost a lot of weight, being almost unrecognizable from her curvier self of before in the series. She’s been on a juice diet for her role in the upcoming “X-Men: First Class.”

Jones and her fellow actresses in “Mad Men” once said they were bound by contract not to lose weight because producers did not want them to become skin and bones like most Hollywood stars.

In recent months, though, she’s been losing a lot of weight, mostly because she’s been on a very strict juice diet, the Daily Mail reports.

The idea was to have her look good in the suit of Emma Frost, whom she’s playing in the upcoming, highly anticipated production.

“As a slender size ten, she had to wear a girdle to match the hourglass curves of her Mad Men co-stars,” the Mail says. Indeed, she had very strong competition in the curves department from the likes of Christina Hendricks, for instance.

“But actress January Jones may need even more help fitting into Betty Draper’s clothes in the next series – after dropping two dress sizes on a strict juice diet,” the British tabloid says.

“The 33-year-old has shrunk to a tiny size six to take on the role of Emma Frost in the upcoming X-Men film,” the Mail informs.

In one of her most recent interview, Jones herself has admitted to losing weight because she wanted to make a believable Frost in “X-Men” and called the journey to a slimmer self a “challenge.”

“In the comic it’s pretty much painted on and she has quite an unrealistic body,” she says, as cited by the aforementioned publication.

Reports in the media suggest that January got this thin as she is now thanks to a diet of juices and raw vegetables. No word yet on whether she plans on staying this thin or will be back to her previous weight just as “Mad Men” starts shooting for a new season.