J.Crew under pressure for offering size 000

Models pose at the J.Crew presentation during Fashion Week, New York.
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J.Crew came under fire on Tuesday following reports that the specialty retailer is now offering items in size 000—the equivalent of an XXXS.

Blogs, including the well-known website Racked and the less high-profile Capitol Hill Style, called out the new size—which compares to a size zero in the U.K. or Australia—as a signal that vanity sizing has gotten out of control.

"I won't support J.Crew's decision to expand their sizing downward because it feeds into the notion that clothing size is a scarlet letter," Capitol Hill Style wrote. "The practical and reasonable thing to do would be to create a measurement's guide that isn't abhorrently dishonest, accepting that the brand now sells size 24 clothing."

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A spokeswoman for J.Crew said the 000 tag has nothing to do with vanity sizing, a practice used by some retailers where they manipulate sizes to make shoppers feel like they wear a smaller number.

"We are simply addressing the demand coming from Asia for smaller sizes than what we had carried. Our sizes typically run big and the Asia market tends to run small," the spokeswoman said. "To further put into perspective, these sizes add up to the smallest possible percentage of our overall sizing assortment."

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"Also to note, J.Crew's sizes run across the board to try and accommodate as many customers as possible… We run up to size 16, we carry petites and talls, and our shoe sizes run from 5-12. [It's] all based on customer demand," she said.

—By CNBC's Krystina Gustafson