MILWAUKEE - Is size 4 the new size 8? With the average American waistline growing, designers are getting creative to keep shoppers buying.

When you go shopping, what makes you buy? Price? How the clothes fit? What about size?

"I think I'm more likely to buy if it's a size two," says Alana Norris.

That's what some designers are banking on.

"Even if a woman is a size two and she wears a size zero, she feels good about it," points out Heidi Calaway, owner of Vieux et Nouveau on Milwaukee's east side.

Calaway sees more designers cutting women's clothes bigger. That's called "vanity sizing”: when the tag says it's a size six but it's really more like an eight.

"I guess the mentality that people don't want is 'oh, I'm wearing a 22' that might have been a 16 back in the day," says Calaway.

Sizing charts tell the story. We looked at measurements for a size six pant at three major retailers. At Old Navy, it's 27 inches. Abercrombie is 28 inches. At Lands End a size six pant measures 28 to 29 inches.

That's feeding women's vanity.

Julianna Olson is a regular customer at Vieux et Nouveau. She usually wears a size large, but Calaway convinced her to try on a size small dress…and it fit.

"I totally did not expect to be in a small and have it look that good,” Olson said.

Calaway says carrying designers that use vanity sizing makes her customers feel good.

"It makes me feel kind of tiny and petite and delicate," Olson said. “It does something to your inner being."

Norris agrees. She typically wears a size four, but depending on the store she can wear a two. That's incentive to purchase!

“If I'm waffling on it, I would probably be more likely to buy it,” Norris said.

TODAY’S TMJ4 sent Norris shopping to see how true to size several bit retailers are. At The Gap, she was a size two. Same story at Eddie Bauer and Ann Taylor Loft.

"I ended up with the two," Norris said. "The four was like falling off."

All these numbers can play with your head and possibly send negative messages to young girls.

"The logical me is saying we're just kind of playing into, you know, lying about our body image and that we should feel bad about what our body image is,” Olson said.

The best advice, buy what fits your silhouette. No matter what the size.