J.Crew is experiencing a backlash from experts in eating disorders after the American clothing retailer introduced a size 000 to its stores.

J.Crew said the new super-small size, meant to fit a 23-inch waist, is in response to demand coming from the Asian market. But critics say the 000 size further fuels society’s fixation with being thin.

"The way we fetishize being thin in society is certainly not new, but it is reaching new extremes in the way we're seeing clothing sized," Jackie Grandy of the National Eating Disorder Information Centre told CTV's Canada AM on Wednesday.

Grandy said the organization does not dispute the size – which is equivalent to a children's size eight typically worn by seven- and eight-year-olds.  Rather, she said the marketing of the clothing is the problem.

In Glandy’s view, size 000 represents an extreme example of "vanity sizing."

"Clothing manufacturers are deliberately using small clothing labels to appeal to that sense of self-worth that many of us still get from wearing a smaller size," she said.

A company that uses vanity sizing could, for example, take a size 6 dress and label it as size 2.

Grandy said the number on the clothing label has a psychological impact on some shoppers.

"For many people self-worth is equated, to some extent, to a clothing label or number on a scale," she said. "When you got these three zeroes in a row, what are we telling women?

"Are we encouraging them to disappear into negative space and to try to achieve new lows in terms of the number they see on the scale?"

Grandy said she'd like to women's clothing sizing labels resemble men's clothing labels, which use inches rather than XS, XL or numbers like 000.

J.Crew has said the 000 clothing accounts for the smallest percentage of its inventory. The retailer has also pointed out that it offers up to a size 20 in some styles, as well as petite and tall clothing to meet customer demand.