Christina Hendricks thin Joan Barbie doll

Christina Hendricks (left), and the Joan Barbie doll (right). Photos: AMC | Courtesy of Mattel

Leave it to Barbie to put Christina Hendricks on a diet.

The world's most famous plastic blonde -- besides Heidi Montag, of course -- has added "Mad Men" character Joan Harris to her stable of collectible playmates but took away her killer curves in the process!

The Joan doll -- part of a "Mad Men" collection that includes Don Draper, his wife Betty, and Sterling Cooper partner Roger Sterling -- has all of the 1960s sexy secretary's signature assets, such as a red updo, a body-hugging purple dress, and a smoldering sideways glance.

But it seems Mattel's Joan has been taking diet tips from Twiggy, because her iconic hourglass figure now looks more like an egg timer!

The release of the Joan doll comes at the same time that Hendricks was hailed by British Equalities Minister Lynne Featherstone for having the "ideal shape" and for being a role model to U.K. women, reports the Daily Mail.

Not surprisingly the pin-thin plaything has upset the British Dietetic Association.

"There is no reason a size 14 can't be healthy and attractive," dietitian Sion Porter tells the newspaper, "so it's sad and alarming that toy manufacturers can't represent this.

But Mattel claims the Joan doll was never meant to break the mold. According to a Mattel spokesperson, "The 'Mad Men' dolls are styled to capture the aesthetics of the show" and not the actress's actual figure, the Daily Mail reports.

Whatever! All we know is that if you put a pink waitress uniform on that doll, she'd look an awful lot like Flo from the 1970s sitcom "Alice."

In related news, read about the no diets/no exercise rule the "Mad Men" women must follow.