Anorexia nervosa might trigger a loss of appetite and extreme desire. Someone with anorexia nervosa attempts to maintain a weight that is at least 15-percent below normal for her age and elevation. Anorexia nervosa is most frequent among adolescent women, even though even adults of all sexes and teen boys may develop this illness. MayoClinic.com says that specific risk factors might raise the chance of developing anorexia nervosa, including youth, female gender, genetics and contribution in certain work, sports or artistic activities.
Diabetes insipidus may cause decreased appetite and increased thirst. Diabetes insipidus is a disorder as they filter blood by which a person's kidneys are unable of preserving water. The volume of water conserved by the kidneys is controlled by anti-diuretic hormone. ADH, also called vasopressin, regulates the re-absorption of molecules in the kidneys' tubules by changing the tissue's permeability. According the MedlinePlus site, there are only two principle types of diabetes insipidus: central and nephrogenic to. Double signs and symptoms associated with diabetes insipidus include decreased appetite, excessive thirst and increased urine volume.