By Jonathan Purtle

Why is it that the fatter America gets, the more unrealistically thin our ideal of what people should look like becomes? It's not just a perplexing paradox. It poses a threat to the public’s health: our nation’s obesity crisis may eventually be coupled with anorexia and bulimia crises as well.

As noted in my post last week, America is in the midst of an obesity era. Thirty-seven percent of adults and 17 percent of kids are obese, and no one is particularly happy about it. All the while, Americans are bombarded with digitally manipulated (a.k.a. “photoshopped”) images of models that are impossibly thin and blemish free.

As highlighted by recent stories by the New York Times and BBC, young women in the U.S. and abroad have began to protest the photoshopped female form and the notion that they should strive for a body that — by virtue of skeletal constraints — is literally unobtainable.

Last summer, the American Medical Association (AMA, which, compared to the American Public Health Association, is a relatively conservative group) adopted a policy discouraging advertisers from using altered photographs that “promote unrealistic expectations of appropriate body image” and have been found to be linked to eating disorders and other adverse health outcomes. One AMA board member cited a particular photo that was altered so that a model’s head appeared wider than her waist. Across the Atlantic, authorities in France and the United Kingdom have considered requiring computer-altered images to be labeled as such.

An estimated 50 percent of girls and young women are dissatisfied with their body image. In 2009, 14.5 percent of high school girls and 6.9 percent of boys reported not eating for at least 24 hours to lose weight, while 5.4 percent of girls and 2.6 percent of boys vomited or took laxatives to keep from gaining weight. “Pro-anorexia” pages on social media sites, such as Tumblr and Pinterest, may provide a more accurate picture of the state of eating disorders in America than what public health statistics can capture.

The evidence linking exposure to images of impossibly ideal bodies to risk factors for poor health is growing. A group of college-age women in one experiment were exposed to “ideally thin” images of women, while a control group was exposed to normal images. The study found that women in the ideally thin group were less satisfied with their bodies, had lower self-esteem, and more eating disorder symptoms than the control group.

While some argue that such research provides justification to regulate altered photographs on public health grounds, the most accessible path to regulation may be in the name of consumer protection. Last summer, the U.K.’s Advertising Standards Authority banned digitally-altered makeup ads featuring Julia Roberts and Christy Turlington because they were airbrushed to the point of being considered false advertising.

So, if we were to decide that computer-altered images of the human form should be regulated, how exactly would we do it? Since some images are more deceptive than others, wouldn't an all-out ban or one-size-fits-all labeling requirement be a bit harsh? Computer scientists at Dartmouth College have a solution.

In a 2011 article in the Proceedings of the National Academy of Sciences, Eric Kee and Hany Farid describe a scale they developed to quantify the extent to which a person’s appearance has been digitally altered. The scale is capable of generating a score that can be displayed alongside altered images — informing the viewer of the degree to which its appearance deviates from reality.

The public health community should advocate for widespread private sector adoption of Kee and Farid's scale in the name of social responsibility, and should press the federal government to explore the costs and benefits of mandating its use. If that sounds radical, try this analogy: the scale is to eating-disorder prevention as menu-labeling requirements are to obesity prevention. Both let you look at, and eat, whatever you want — but at least let you know what exactly it is that you're putting in your mind, and your body.

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