Although there are cases where an anorexic's body weight suddenly drops by 15 % or more over just a few weeks, the medical profession uses three or more consecutive months without a menstrual period as one of the diagnostic thresholds for anorexia.
雖然也有幾週內體重突降 15 % 以上的案例，但醫學上做為厭食症判斷標準的，還需有連續 3 個月以上無月經現象。