I found this a while ago. I found it on an online blog, its several years old by now but it interesting to read what we knew or didn't know about the causes of Anorexia.
The causes of anorexia are rather complex and not easily reduced to
a single primary cause. Here are some factors that appear to be
correlated with the onset of anorexia with supporting citations.
1. Depression and anxiety (Hinz and Williams, 1987, Psychological
Bulletin, 150-158. Anorexia appears to be co-incident with affective
disorders such as depression and anxiety. Some researchers propose that
anorexia is just one specific manifestation of these more general
disorders and by treating the underlying disorder, the manifestation
will disappear. This is not inconsistent with the media hypothesis, in
that highly anxious and depressed patients are more susceptible to
receiving messages and acting on those messages to assuage the anxiety
(the psychic hotline phenomenon).
2. Family characteristics. Anorexic patients families have higher than
normal incidence rates of alcoholsim, obesity, depression. They are
also more middle and upper-class, more competitive, high-achieving and
protective. They often set high standards for their children, and are
intensely concerned with how others perceive them (Pate et al., 1992,
Journal of the American Academy of Child and Adolescent Psychiatry;
Yates, 1990, same journal; Heatherton and Baumeister, 1991,
Psychological Bulletin). Obviously, a fairly narrow band of family
typologies typically give rise to anorexia. Some researchers point out
that this fits the specific manifestation theory of anorexia as a
consequence of a generalized affective disorder. None of these families
would be considered highly dysfunctional relative to the more severe
kinds of dysfunction that is observed (e.g. incest and violence).
Anorexia may then be conceptualized as a manner of meeting the family
values in a socially acceptable and hidden manner.
3. Genetics. When one twin has anorexia, the chances of the other twin
sharing the disorder are much greater if the twins are identical than if
they are fraternal (Fichter and Noegel, 1990, International journal of
eating disorders). A behavioral genetics analysis suggests that some
small, but appreciable amount of variability may be explained by genetic
predisposition. Of course, twins also share parents; yet, shared
enviromental factors (i.e. parents) account for only about 10% of the
phenotypic expression of anorexia. So, parents ARE NOT UNEQUIVOCALLY
the cause of anorexia, but have only a small, albeit significant role in
4. Biochemistry. Anorexics are known to have neurotransmitter
deficiencies not unlike that experienced by depressive and anxious
patients. Thus, drug treatment may prove effective to a limited extent.
Of course, we now know that neurotransmitter production can be
influenced by experience, so the direction of the causal arrow is still
unknown at this time (Fava et al., 1989, American Journal of
5. Weight-conscious culture (Pike and Rodin, 1991. Journal of Abnormal
Psychology). Mothers of anorexic girls are more likely to be obsessed
with their own weight and with their daughters appearance.
Interestingly, the effects of fathers influence is thought to be rather
minimal, at best. Again, this does not suggest that the cause lies with
the mothers directly, but it may lie with cultural influences
transmitted through the mother.
6. Peers (Crandall, 1988, Journal of Personality and Social
Psychology). Crandall provides data which supports a model of social
contagion, in that anorexia and binge-eating appear to spread in ways
that are consistent with epidemic models of disease spread. Thus, peers
provide the carrier mechanism which increases the incidence rate.
Crandall suggests that peers are more associated with anorexia onset
7. Cognitive distortion (Fallon and Rozin, 1985, Journal of Abnormal
Psychology). Women have distorted impressions of what men find
attractive. A woman's idealized body weight was much lower than her own
current body weight; likewise her perception of what weight men
preferred was much less than the weight men actually preferred; and the
weight men actually preferred was actually only a litle bit less than
what the average woman currently weighs. Apparently, for men the
idealized weight, current acstual body weight, and the perception of
what women prefer showed no discrepancies (self-delusion being a good
thing?). Apparently, the source of this greater self-dissatisfaction
among women could be explained by their perceiving their hips as being
8. Cultural images (Brownell, 1991, Behavior Therapy).
-- American models today weigh 23% less than the average woman, making
them in the bottom 5% for weight of all women.
-- in 1950, dept. store mannequins reflected the average woman of the
time. Since then, they have lost about 3 inches around the hips, which
together with the higher fat diets we now eat, giving mannequins a 31 in
hip versus the 37 inch hip of the average American woman (see previous
paragraph concerning cognitive distortions).
-- Today, the average American woman weighs 40 pounds more than the
woman of 1950, but Miss America contestants weight 15 pounds less on
average than their counterparts of 1950.
--- Most models and actresses today have less than 1/2 the body fat of
the normal woman (10 to 15% versus 22 to 28%).