Obese people are showing up in the very place that's mostly excluded them for decades: ads.

Someof the nation's largest brands ? from Nike to Subway to Blue Cross BlueShield ? are featuring images of obese or overweight folks in theiradvertising in a bid to change consumer behavior. (Obesity is consideredto be anything 20% or more over ideal weight.)

The move comes at atime almost two in three adults are overweight or obese, and diseasescaused by obesity cost Americans $145 billion last year. In the past,when obese folks showed up in ads, they were often the butts of jokes.Now, they're visual images for change.

Why is it now acceptable toshow obesity? "More of us are overweight, so it's a shared problem,"says Valerie Folkes, marketing professor at University of SouthernCalifornia.

It's a generational thing, too, says brand consultantErich Joachimsthaler. "The new generation doesn't see (obese people) asdifferent. There is a new, democratic world view: Everyone can be astar."

Among those showing obesity:

* Blue Cross Blue Shield of Minnesota. The health provider has two new ads with obese actors. In one, anobese father with a tray full of fast food thinks twice when heoverhears his large son arguing with a fat friend over whose father caneat more. The second features a young girl following her mother in thegrocery store and picking up the same junk food and putting it in herkiddie cart.

"People have to make choices about food every day," says MarcManley, chief prevention officer. "We want to give them encouragement tomake healthier choices."

* Nike. The shoemaker launched an ad this summer showing an obese runner jogging.

"It's not just championship athletes that aspire to push their limits," spokesman KeJuan Wilkins says.

* Subway. In March, the sandwich chain will celebrate the 15thanniversary of Jared as its spokesman by congratulating him forkeeping svelte. The ads will feature old photos of him at 425 pounds."It's hard to lose the weight, but it's even harder to keep it off,"says Tony Pace, head of Subway's marketing arm.

But the messagecan get murky, says James Zervios, spokesman for the Obesity ActionCoalition, a non-profit representing obese people. "It's a fine line,"he says, noting that marketers need to be careful of stereotypes linkingall obesity to overeating. "So far, they're staying on the positiveside of the line, but it's easy to cross over."