Shapewear Dresses May Be Secret Weapon to Slim Look

When Christy Messina looks in the mirror, she still sees the weight she put on when she was pregnant with her infant son, Wes.

"That's the area I'm insecure about," she says, pointing to her stomach and bottom half.

Priscilla Mota says she sees a tummy that's just not flat enough.

"I would love to smooth out the kangaroo pouch," Mota says.

And Julie Sabatino says she wishes she had a smaller bottom half. "I'm pear-shaped, so I'm very insecure in that area."

The solution to all of these women's body image worries, says fashion designer Shani Grosz, isn't diet or even exercise, but her line of what she calls "miracle dresses" which have shape wear built in to smooth a woman's body and instantly create a slimmer figure.

"Our dresses are designed to make a woman look 10 pounds thinner or one size smaller," Grosz said about her line of Nue by Shani dresses. Grosz says the dresses are selling like hot cakes.

That doesn't surprise stylist Pamela Pekerman, who says dresses designed to make women look thinner are more in demand now than ever before. As long as women want to look flawless, this trend is not going away.

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But can a dress really make a woman look and feel 10 pounds lighter and one size smaller? "Good Morning America" decided to find out, rounding up six women, sizes 2 to 16, to try on different dresses that claim to flatter the figure.

First, women tried on a royal blue dress from Nue by Shani. The women agreed the blue dress eliminated their so-called "muffin tops" and other problem areas.

"I feel very confident. It really sucks things in and smoothes things out," one woman told us.

Before donning the frock, Lauren Czerwinski's waist was 30 inches wide and her hips 41 inches. After putting on Shawnee's dress, the mom lost two inches in both areas.

The second option, a nylon-spandex black dress from Sassybax, which retails for $76 and can be worn as a tube dress or a skirt, was also a hit with the women. Czerwinski lost even more inches in the Sassybax dress. This time, her hips were just 38 inches - three inches slimmer than without the shape wear dresses.

"I feel like I'm in my 20s again," she said. "It's a miracle!"