Anorexia
nervosa is a very destructive disease. If it doesn't kill you, it often makes you wish it has. It destroys you- mind, body, and spirit.
So how on
Earth could anorexia serve an adaptive function? It's a deadly disease. Except that certain
traits of anorexia could be adaptive, if you think of humans as hunter-gatherers, nomads collecting roots and berries and the occasional
auroch.
At the risk of overgeneralizing, people with anorexia have an easier time avoiding food than other people, withstand starvation better, and are hyperactive (especially during the acute phase of illness). In a time and place where food isn't a guarantee, these things can be beneficial to the human species as a whole.
In her "
Adapted to Flee Famine" hypothesis, psychologist
ShanGuisinger writes that these "distinctive symptoms" of anorexia
nervosa are
likely to be evolved adaptive mechanisms that facilitated ancestral nomadic foragers leaving depleted environments; genetically susceptible individuals who lose too much weight may trigger these archaic adaptations. This hypothesis accounts for the occurrence of AN-like syndromes in both humans and animals and is consistent with changes observed in the physiology, cognitions, and behavior of patients with AN. (The entire paper is about 17 pages, but well worth the read)
A
new paper out in the Annals of the New York Academy of Sciences takes an evolutionary look specifically at the
overactivity aspect of this trio of symptoms.
CPArun writes
Some patients with AN exhibit overactivity that can worsen their state of malnutrition. Employing an evolutionary psychiatry line of inquiry, we propose that rigidity of thinking and overactivity are behavioral phenotypic changes in AN patients that are normal to tree-dwelling mammals, such as monkeys. Such behavior can lead to good functioning as ballet dancers and athletes but lead to certain disadvantages in other areas of modern life. The overactivity in AN, though under conscious control may be neurobehavioral and driven subconsciously by disordered cerebral neuropsychopharmacology. Though I might debate exactly how much "conscious control" a sufferer has, seeing these traits as potentially adaptive at another time and place helps me take a little bit of the mystery out of this illness.
So how on Earth could anorexia serve an adaptive function? It's a deadly disease. Except that certain traits of anorexia could be adaptive, if you think of humans as hunter-gatherers, nomads collecting roots and berries and the occasional auroch.
At the risk of overgeneralizing, people with anorexia have an easier time avoiding food than other people, withstand starvation better, and are hyperactive (especially during the acute phase of illness). In a time and place where food isn't a guarantee, these things can be beneficial to the human species as a whole.
In her " Adapted to Flee Famine" hypothesis, psychologist ShanGuisinger writes that these "distinctive symptoms" of anorexia nervosa are
likely to be evolved adaptive mechanisms that facilitated ancestral nomadic foragers leaving depleted environments; genetically susceptible individuals who lose too much weight may trigger these archaic adaptations. This hypothesis accounts for the occurrence of AN-like syndromes in both humans and animals and is consistent with changes observed in the physiology, cognitions, and behavior of patients with AN.
(The entire paper is about 17 pages, but well worth the read)
A new paper out in the Annals of the New York Academy of Sciences takes an evolutionary look specifically at the overactivity aspect of this trio of symptoms. CPArun writes
Some patients with AN exhibit overactivity that can worsen their state of malnutrition. Employing an evolutionary psychiatry line of inquiry, we propose that rigidity of thinking and overactivity are behavioral phenotypic changes in AN patients that are normal to tree-dwelling mammals, such as monkeys. Such behavior can lead to good functioning as ballet dancers and athletes but lead to certain disadvantages in other areas of modern life. The overactivity in AN, though under conscious control may be neurobehavioral and driven subconsciously by disordered cerebral neuropsychopharmacology.
Though I might debate exactly how much "conscious control" a sufferer has, seeing these traits as potentially adaptive at another time and place helps me take a little bit of the mystery out of this illness.