One day last year, Amanda Coleman decided to quit Facebook. It wasn't one precipitating event that led her to her decision, but a slow build -- a series of disturbing, sometimes anguished conversations. Coleman, a college student and the president of her sorority, found herself spending a lot of time counseling young girls, many of them freshman at the university. "They would call or come in to see me for advice, crying that they were stressed out," she said. As it turned out, the insecurities that bedeviled the girls were often fueled by social networking sites. "At some point I began noticing that Facebook was being mentioned in some way in just about every conversation." She said the girls knew they were in college to study, but they were spending hours on the computer, obsessing over photos and status updates, and comparing themselves to their friends and their friends' friends. What's changed? Before social networks, we mostly had images of impossibly perfect celebrities. We would pass these images on billboards, watch them on TV, flip through them in magazines, but we weren't sitting around staring at them for hours every day. "And, you know, at some level we all knew these were models and celebs, so maybe it was different somehow, more fictional and unattainable," said Coleman. Because of social networks, though, the field of competition has expanded dramatically. Now you're competing with the best pictures and the ebullient status updates of every girl you know. "It's as if somewhere along the line, Facebook became the encyclopedia of beauty and status and comparisons." It didn't stop there. Among some of Coleman's girls, the constant self-comparisons and escalating insecurities translated into a pattern of food deprivation and incessant exercise. "They were walking around saying, 'I'm not good enough. I'm not enough this or that.' And I guess what they had the most control over was their weight." That's when the other, more pernicious social networks came into the picture. Some of the girls in Coleman's sorority began frequenting pro-eating-disorder communities online, where users encourage one another in anorexic and bulimic behavior. Most of these sites, open to all, offer "thinspiration" (or "thinspo") -- photographs of emaciated celebrities and models, and before-and-after shots of girls-next-door, meant to serve as motivation on the quest for skin and bones. "It was like this slippery slope from regular social networking sites to the eating disorder ones," said Coleman. She also found that the feelings of insecurity were oddly contagious, even spreading among groups of friends who normally had a healthy body image. "Social networking sites are part of the ubiquitous media landscape that shapes what children come to know as society's body ideal," observed Dina Borzekowski, professor at Johns Hopkins Bloomberg School of Public Health, who specializes in children, media and health. "Social media may have a stronger impact on children's body images than traditional media. Messages and images are more targeted; if the message comes from a 'friend,' it is perceived as more credible and meaningful." What's more, we're now dealing with a fluctuating scenario where the people we're most worried about are actually creating the media itself. "When you're talking about unhealthy behaviors like eating disorders, suicide and depression, and maybe even violence, there are other young people who are giving instruction and support, toward both positive and negative behaviors," said Sahara Byrne, assistant professor of communication at Cornell University. "It's the young people who are creating a lot of this, for better or worse. By comparison, body image issues in magazines now seem very quaint and uncomplicated." Conflicting conclusions Though the effects of social networks on self-esteem, self-image and body image is an area of significant interest, there have only been a handful of mainstream studies, focused almost exclusively on Facebook. The findings appear to be largely conflicting. Some claim that Facebook boosts self-esteem, while others report the opposite, including a condition known as "Facebook depression." It's also tough to validate the theory of a "slippery slope" between mainstream social networks and an elevated risk for eating disorders, though one compelling 2011 study from the University of Haifa found that the more time adolescent girls spent on Facebook, the more likely they were to develop a negative body image and eating disorders. Regardless, Byrne said, it's a problem when perverse behavior is rewarded by people you trust and relate to. "If you have a girl put up a photo of herself very thin and scantily clad, and a slew of comments tell her she looks 'beautiful' or 'hot,' that's where you run into problems because others might seek that same reward." Media susceptibility Some young people do feel anxiety about idealized self-presentations on Facebook, observed Alice Marwick, Ph.D., a postdoctoral researcher in social media at Microsoft Research New England. But, she says, "plenty of teens have no problems integrating these things into their lives. Most are navigating it very gracefully." "My work errs on the side of giving kids the benefit of doubt," said Marwick. "Rather than pathologizing children, we need to look at what messages we are sending in mainstream culture. There are some systemic issues at play here and we can't put the blame on individuals. We are living in a culture with extremely dysfunctional attitudes about weight." According to Marwick, sites offering "thinspiration" are not new. They've been around for at least a decade. And there's not an enormous difference between regular weight loss sites and thinspiration sites -- they are usually sending the same message: the importance of looking a certain way, counting calories and exercising a lot. Borzekowski's work supports the notion that pro-eating-disorder sites are not quite so black and white. In 2010, she and her colleague, Dr. Rebecka Peebles, presented the findings of their study, which is described as the first large-scale analysis of pro-eating-disorder websites. They concluded that the sites spanned a diverse continuum between hard-core information about how to intensify an eating disorder, pro-recovery content and a mix of both. What's more, noted Borzekowski, the media landscape has evolved significantly in just the past two years. A great deal of eating disorder messages are now being delivered through Twitter, texts and Tumblr. But these platforms are also being used to deliver positive messages. In recent history, some of the younger celebrities have engaged in Twitter skirmishes to denounce cultural elements that can fuel eating disorders. Last November, on the heels of a barrage of cruel, misogynistic jokes and YouTube videos about her weight, 18-year-old Miley Cyrus posted a photograph of an emaciated woman alongside a Tweet that said: "By calling girls like me fat, this is what you're doing to other people." She also shared an image of Marilyn Monroe with the caption, "Proof that you can be adored by thousands of men even when your thighs touch." Demi Lovato, who was treated for depression and an eating disorder in 2010, has used Twitter to strike back at flippant jokes about eating issues. In a recent documentary, Lovato admitted that she has relapsed a few times since treatment and that while she may never fully recover from her issues, she is doing her best to keep them under control. Critical role of supportive adults In general, observed Borzekowski, "there are people who are much more susceptible to media's influence than others. Messages and images like thinspiration pictures may inspire some but repulse others." In her experience, children who are most at risk are those with more exposure to media messages, and less exposure to rational, clear messages from supportive adults and community leaders. The heaviest users of media are the ones who have the most distorted beliefs about society. However, Byrne's research shows that the more parents try to restrict media use with the kids, the more kids will try to find ways around it or seriously resent their parents because they feel they are not being allowed to take part in the greater cultural conversation. This, noted Byrne, may go on to cause a whole host of other problems. When it comes to technology, children and family dynamics are changing drastically, said Byrne, and we're just going to have to react for a while. Not all of our children will make it through without big, awful bruises. Borzekowski believes parents need to be more aware of the messages reaching their children and adolescents. "How many parents can really say they've seen the YouTube videos their teen has seen in the last two to three days?" she said. "Parents need to be able to tell their kids to put their smartphones away." But they can't be hypocritical, Borzekowski warned. Parents "need to put their phones away, too." Studies show that the earlier parents start a conversation with their children about the online space, the better. "Anytime a child reports that their parent is hard to talk to about the Internet, that is correlated with all sorts of problems, including things the kids should not be doing online," said Byrne. "We as parents do not know everything about this space, but we can ask questions. Begin talking to children about social media at 6 or 7." It's not easy, she said "I had a hard time creating that in my own household." Byrne admitted. "But I know that when my daughter did run into trouble, she came to me and knew that I would not be shocked. (Even though I was! But I didn't let on!)" What we can hope for is that there are small-scale lessons to be learned early on, experts say. If we make smaller mistakes, we have the opportunity to talk about consequences and then hopefully avoid the bigger mistakes. Coleman, who's now a college senior on the verge of graduation, said she recognizes that social networks are a huge tool for communication and being connected. "But unfortunately they've also taken on the role of teaching girls to depict themselves in a certain way and to constantly compare themselves to each other," she said. "Maybe we need a new way of teaching young people about privacy and discretion and moderation, and that maybe sometimes less is more."