The literal answer to your question is "no" (for virtually all psychological phenomena there are many contributing factors—rarely ever a single cause), but I think your followup question is a better question on which to focus: "what is the actual relationship between eating disorders and those unrealistic body images in media?" As you could imagine, this is a highly researched area—with mixed results. There was a meta-analysis that looked at a similar question back in 2004 and found that, overall, the media's portrayal of thin women had virtually no effect on body image, although portrayal of overweight women did have a positive effect (Holmstrom, 2004). A more recent meta-analysis by Hausenblas et al. (2013) found small effects for media exposure—especially for participants already at high risk for developing an eating disorder. To sum up the research, I would conclude that the layman's concern for the media "causing" eating disorders is highly exaggerated and scientifically without merit. My advice—we need to focus more on teaching critical thinking than trying to control the media. Critical thinkers understand that they are being sold an ideal (usually Photoshopped), not a reality.Response: I agree that eating disorder is not caused by any single factor but by a combination of complex factors. But can media be one of those causes? I think before going further, what we need to confirm first is: what is a causal relationship? what criteria it takes for something to be a cause of something else? :)
In the cases where the media does appear to have a measurable effect on how people perceive their body images, the media would be considered a "moderator." This could be stated as "the media has been shown to have a moderating effect on how people perceive their bodies." Rarely would you see "X causes Y" in psychology—these kinds of statements usually originate from the mass media attempting to dramatize conservative findings of researchers. A causal relationship (focusing on psychology here) can only be established with true experimentation (quasi-experiments can make weak inferences to causality). Even then, causality is probabilistic, unlike the physical sciences—correctly stated as "our research suggests that X is a causal factor for Y." Again, it is the methodology that establishes the likelihood of causality. True experimental designs are difficult, expensive, unethical or even impossible in most cases in psychology, so we make due with correlations. Hope that helps!
Hausenblas, H. A., Campbell, A., Menzel, J. E., Doughty, J., Levine, M., & Thompson, J. K. (2013). Media effects of experimental presentation of the ideal physique on eating disorder symptoms: A meta-analysis of laboratory studies. Clinical Psychology Review, 33(1), 168–181. doi:10.1016/j.cpr.2012.10.011
Holmstrom, A. J. (2004). The Effects of the Media on Body Image: A Meta-Analysis. Journal of Broadcasting & Electronic Media, 48(2), 196–217. doi:10.1207/s15506878jobem4802_3
Bo Bennett, PhD
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