Serious anorexia (eg. Anorexia nervosa) is actually a systemic
vascular problem also called multiple system atrophy. Other
symptoms include insomnia, hypotentosion, orthostatic-intolerance
which all lead to a diagnosis of arterial tone loss due to vascular and
organic changes. The underlying medical condition common with
several other (improperly) so called "mental illnesses" is the
"endothelial dysfunction". Only gene therapy in very young people
can give them a change to survive.
Do not believe that it is cause by bad habits or cognitive impairment.
Hunger, like breathing, is not much influenced by the cognitive
function. Their body gets wasted because they were born with
significant arterial abnormalities and their body cannot be nourished
and oxygenated regardless how many calories they eat.