I can not imagine that eating disorders would be contagious, maybe if there is a history of depression, that would make more sense . Please advise

Yes, I believe eating disorders can be "contagious". I assume the word "contagious" here is not being used in the medical sense (like a disease being transmitted), yet in the non-technical term: a contagious laugh.

Eating disorder studies continue to suggest that there still are no concrete "causes" that can be pinpointed as to why some people develop an eating disorder, and others do not, but many "factors" are related to eating disorders.

One of these factors may be genetic. If we use the "contagion" analogy, then the question becomes one of nature/nurture: do eating disorders "run in families" from being inherited or from experiencing the behavior in the home. The answer could be BOTH; studies are suggesting that there may be an "eating disorder" gene or chemical imbalance that is inherited. Mental illnesses also occur in families, like depression, which is a contributing factor in developing an eating disorder. It also makes sense that the disordered eating behaviors may be learned in the home, as eating disorders effect the entire family.

The environment plays a large role in ALL of our behaviors, and eating issues, including eating disorders, are not excluded. Environmental and cultural factors can include such "contagions" as stressors (living environment has changed), some of our media images (airbrushed models on magazines and TV) or a "social norm" to be thin.

Girls are dieting in groups (which would not be a far leap for them to also binge-and-purge, or avoid eating, in groups). Girls are also "feeling fat" at younger and younger ages and wanting to lose weight. These are all warning signs of disordered eating patterns.

The "clustering" of behaviors isn't new. People tend to befriend like-minded people, who have similar interests, values and behaviors. Think about how many smokers "hang out" together, how many runners tend to "run in groups" (sorry for the awful pun). Same for eating behaviors: over-eating and under-eating may happen in groups. (Healthy eating also happens in groups!)

Please know: the above discusses only a few factors in how eating disorders manifest themselves. People living with anorexia, for example, tend to hide their eating and may not eat in groups. Similar to depression and many other health topics shared on this website, many of these issues make people feel shameful, guilty and embarrassed; therefore, are not disclosed to others. They are purposefully and skillfully hidden. Eating disorders are more than just about food; they are real mental illnesses that people can recover from with appropriate care from physicians, nutritionists and counselors.

For more information about eating disorders, visit the National Eating Disorder Association (NEDA) at www.neda.org