The thin woman in the red bathing suit in the Special K cereal commercials can quit checking herself out in the mirror. She can even start her day with a Danish.

That's because Special K is replacing her with plus-sized women, at least in England.

The new campaign is supposed to help women focus on positive factors surrounding weight loss other than just their appearance, a Special K spokeswoman said.

The models -- who will be real women rather than professional models -- will have Body Mass Index (BMI) numbers of up to 29. (A BMI of 25 to 29.9 is regarded as overweight. Anything 30 or above is considered obese.)

"We want to encourage a responsible attitude when it comes to body image and to show that losing weight isn't just about the way you look or a certain size you need to conform to, but more importantly about the way it makes you feel," said the spokeswoman. "The fact that we are using real women for the first time of a variety of shapes and sizes is the perfect way to encourage women to think differently about losing weight and not just focus on the numbers on the bathroom scales."

The Centers for Disease Control and Prevention says the average weight for American women over age 20 is 164.7 pounds with a 37-inch waist.

So, what exactly qualifies as plus size?

There's quite a bit of debate about that. The average dress size is a 14, but in clothing stores sizes as small as 12 may be considered a plus size. And while the average model wears a 6 to size 2, plus-sized models can be anywhere from a size 6 to a size 16, according to

Dove and several other U.S. companies have been using plus-size models and real women in ad campaigns for years. But it's unclear if a flood of other companies will follow suit.