When teenage girls check out Seventeen magazine, they'll be getting the complete picture -- no ifs, ands or Photoshopped butts about it.

That's the pledge the magazine's staff made in its latest edition, after a push led by a Maine 14-year-old to combat the practice of tweaking pictures and picking models whose appearance give teens an unrealistic perspective on what is beautiful.

"We vow to ... never change girls' body or face shapes. (Never have, never will)," the magazine states as part of its "Body Peace Treaty" from its August edition, a copy of which CNN obtained Thursday.

The treaty and accompanying note by editor-in-chief Ann Shoket promise that Seventeen will "celebrate every kind of beauty" and feature "real girls and models who are healthy," while vouching that the magazine always has done just that.

But the more than 84,000 people who signed a Change.org petition, started by teenager Julia Bluhm, clearly believed Seventeen and other publications didn't always present the full, unvarnished truth.

"Those 'pretty women' that we see in magazines are fake," the petition said, in requesting "one unaltered -- real -- photo spread per month." "They're often Photoshopped, air-brushed, edited to look thinner and to appear like they have perfect skin. A girl you see in a magazine probably looks a lot different in real life."

Retouching photographs is nothing new -- especially in magazines and, increasingly, on the Internet. Adobe Photoshop and other digital image manipulation programs are widely employed by professionals and everyday users.

The petition claims that disseminating such altered images to impressionable teens can pose a real danger, helping to spawn a culture that touts unrealistic beauty and contributes to eating disorders, extreme dieting, depression and more.

"I know how it affects girls and ... my friends," Julia told CNN in May, shortly after meeting with Shoket and presenting the signatures to her. "We don't realize it sometimes when we're just looking at the magazine and having fun. It can lower self-esteem."

But not all teenage girls think retouching photographs is a problem.

Alexis Jones of Alpharetta, Georgia, said Thursday she'd worry that, if magazines portrayed young women who were overweight or had acne as being beautiful, some girls may think it's OK to live an unhealthy lifestyle. In fact, she feels making models' bodies thinner and their skin clearer can serve as positive motivation for people to take better care of themselves.

"Some people use that ideal image as motivation to get fit, eat healthy and stuff, while some use it as a crutch," said the 18-year-old, a rising freshman at Georgia State University. "You just have to be strong-minded."

In addition to going "more public" in its commitment, Seventeen states in its latest edition it is partnering with the National Eating Disorders Association and the Commission for Positive Images of Women and Girls.

The magazine's treaty also vows it will "be totally upfront about what goes into our photo shoots" and it understands that, "regardless of clothing size, being healthy is about honoring your natural shape."

"We vow to ... give you the confidence to walk into any room and own it. Say bye-bye to those nagging insecurities that you're not good enough or pretty enough."

Even as she pushed another petition urging Teen Vogue to make a similar public pledge, Julia celebrated the proposals made by Seventeen.

"'Seventeen' listened!" she said in an update of her online petition. "They're saying they won't use Photoshop to digitally alter their models! This is a huge victory, and I'm so unbelievably happy."

The magazine said that it will continue make small changes to photos, like erasing a stray hair or changing background colors, even as it insists it still won't make big changes to a person's body or face.

Yet by not taking any responsibility for having presented anything but "authentic" beauty in the past, the magazine "doesn't really address (the) criticism" from many that it hasn't always lived by those rules, said former model Jenna Sauers.

"Seventeen essentially says that it's never had any issues with the way it's Photoshopped ... celebrities and models but that, just to be on the safe side, it will continue not altering the bodies of the people photographed," said Sauers, a contributor to the female-focused, commentary-driven online magazine Jezebel.com. "It seems like 84,000 people who signed that petition seem to be of the opinion that there were some issues."