Interest in the biological underpinnings of eating disorders, especially bulimia nervosa, has largely focused on the role of the neurotransmitter .

serotonin

Explanation:

Serotonin is the neurotransmitter related to control de mood, appetite, and impulse regulation,  for these reasons it is believed that serotonin levels are low in patients with bulimia nervosa. Tryptophan is an amino acid that we get from food and this is a precursor of serotonin turning this into a circle,  the patient with bulimia nervosa vomits the food reducing the consumption of tryptophan which in turn reduces the production of serotonin. Low serotonin levels may also be due to a genetic factor, making bulimia nervosa a multifactorial disease;  all this without including the psychological factors involved.

Interest in the biological underpinnings of eating disorders, especially bulimia nervosa, has largely focused on the role of the neurotransmitter serotonin

Explanation:

Bulimia nervosa's exact cause is still unknown, but physiologically it may be caused by an abnormality of serotonergic (serotonin-related) neuron functioning and abnormal levels of many hormones ,especially serotonin thus the stress caused by dieting lead to binge-eating leading to purging.

Hence, Interest in the biological underpinnings of eating disorders, especially bulimia nervosa, has largely focused on the role of the neurotransmitter serotonin.

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