CHICAGO (CBS) — Women wear their bras for up to 16 hours a day, but they may not be doing the job.

As CBS 2’s Susan Carlson reports, surveys show 85 percent of women are wearing the wrong bra size.

To the rescue is Susan Nethero, a woman who is known for her appearances on the Oprah Winfrey Show and as founder of the store Intimacy, and who has earned the nickname, “The Bra Whisperer.”

“It’s all about making every woman feel confident in her own body,” Nethero said.

So what is the most common mistake that women make when they buy a bra?

“Our logic would take us in the wrong direction,” Nethero said. “So most women, looking and seeking comfort, are actually getting a bra that’s too big around.”

Cases in point – three brave models, who were willing to “take it off” to teach us the bare facts.

The first model, Krista, had a low bustline, proof for Nethero that she wasn’t getting enough fit.

She also had another common problem, a lumpy back. Nethero says this happens because the band is too loose and rides up.

“(The back) is the leanest part of every woman’s body, so if you bring your bra lower on the body, you won’t see any back fat at all,” Nethero said.

Krista lost four sizes in the band, and went up three cup sizes from 38DD to 34G. And her back fat was no longer in sight.

Model Angelica, in Nethero’s words, was “splaying east and west.”

The wrong size made her centerpiece too wide. But when she went from a 34D to a 32E – again, smaller band and larger cup – the bra fit firmly and provided much more uplift.

And the booby prize – as it were – goes to Nikki, who was wearing a really bad, but all too common, sports bra.

Nethero replaced her 36B with a 32D.

“By bringing her breasts together and centering her bustline – 1 inch is the ideal center definition – all of a sudden, you have breasts!” Nethero said.

Nethero says women change bra sizes about six times in their lives, based on hormonal and weight changes, and distribution shifting over time. As a result, women should get professionally sized every year or so.

Another tip – hook your bra before you wash it, and never put it in the dryer. It ruins the elastic and shape.

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