The spread of a pandemic is typically measured through means and ease of transmission. For instance, viruses can be spread by a cough or sneeze like the influenza virus or by the commingling of blood as in HIV. The reasons why other illnesses become more common, such as autism or celiac disease, are unclear although many hypotheses, with little rationale, abound. But the spread of eating disorders is even more perplexing. These illnesses began out of the blue about forty years ago as afflictions of the wealthy and moved downward through the socioeconomic classes to reach the entire population.
Several related factors lead to someone becoming ill with an eating disorder. First, there is a clearly proven genetic susceptibility to these illnesses. This isn't to say that a gene confers a life sentence to Anorexia or Bulimia. Instead, people with a certain set of genes have a much higher likelihood of getting sick based on the circumstances in their lives. This genetic risk is evident in the striking similarities between people with eating disorders. Personality traits such as rigidity, perfectionism and black-and-white thinking are pervasive, and an innate ability to withstand starvation differently from most of the population triggers the physical and psychological manifestations of an eating disorder.
When an illness is not completely genetic in nature, then life exposure becomes the risk factor as to whether the person contracts the disease. The risks associated with eating disorders include early exposure to food and weight as a critical aspect of life, severe life stress and social isolation. The foremost risk factor that explains the socioeconomic trends in the incidence of eating disorders is prolonged starvation. The pressure for dieting, thinness and starvation began as an upper class experiment largely in response to the changing food environment and the media blitz of emaciated models in the 1960's and 1970's. The culture of starvation, not a brief fad, extended through media and societal pressure into a multi-generational imperative. Recent decades have shown that dieting is now a widespread obsession of all classes. The other risk factors, personal stress or social isolation, for developing eating disorders existed forty years ago, but it's the inculcation of all socioeconomic classes into the culture of dieting that triggered the explosion of eating disorders in the entire population.
Prolonged restriction of food intake triggers a biological evolutionary response based on generations of experience with famine. Natural selection determined that people adapted to best survive prolonged hunger survived, and their genetic adaptations have continued through the ages. Survival could mean several possible metabolic adaptations, for example, more efficient use of energy lowering caloric needs or more effective energy storage during times of plenty leaving a reservoir for lean periods. One's biological reaction to starvation, a primarily genetic function, determines an individual's reaction to the risk factor of starvation. Eating disorders don't choose by class. The epidemiology of eating disorders simply followed the path of starvation.
The critical difference between the classes is access to treatment. All data points to a need for early, complete intervention to decrease the chance that an eating disorder becomes chronic. With few treatments being reliably effective, especially for Anorexia Nervosa, the options recommended by experienced clinicians are time-intensive and prohibitively expensive. Moreover, health insurance rarely covers more than a fraction of most effective options, if they'll cover anything at all. There is no quick fix, no medication cure, no short-term treatment option. Any experienced practitioner knows the path to recovery is long and arduous and demands a dedicated and knowledgeable treatment team. And that costs money.
The wealthy people with eating disorders suffer as much as the poor. I want to be clear about that. The opportunity to attend expensive treatment facilities certainly doesn't guarantee recovery, although it does offer a greater chance to regain weight, stabilize eating and start the process of getting effective, long-term help. Instead, the current system condemns the lower socioeconomic sufferers to limited care with a much higher risk of remaining sick for the long term. Eating disorders may no longer be afflictions of the rich--most of us diet these days and unwittingly tempt our evolutionary fate--but the poor who do get sick are left without any accessible treatment.
The solution relies on a collaboration between low-cost insurance plans and the larger private and hospital-based treatment facilities. These large bureaucracies can form an agreement to provide care to the sufferers with eating disorders but without means. There are powerful eating disorder organizations--ANAD, AED and NEDA--with enough clout to further this discussion and educate the interested parties about how inadequate the affordable options for treatment really are.