Bulimia also has negative effects on a persons teeth due to the acid passed through the mouth from frequent vomiting causing acid erosion, mainly on the posterior dental surface. Research has shown that there is a relationship between bulimia and narcissism. According to a study by the Australian National University, eating disorders are more susceptible among vulnerable narcissists. This can be caused by a childhood in which inner feelings and thoughts were minimized by parents, leading to "a high focus on receiving validation from others to maintain a positive sense of self".The medical journal Borderline Personality Disorder and Emotion Dysregulation notes that a "substantial rate of patients with bulimia nervosa" also have Borderline personality disorder.A study by the Psychopharmacology Research Program of the University of Cincinnati College of Medicine "leaves little doubt that bipolar and eating disorders—particularly bulimia nervosa and bipolar II disorder—are related." The research shows that most clinical studies indicate that patients with bipolar disorder have higher rates of eating disorders, and vice versa. There is overlap in phenomenology, course, comorbidity, family history, and pharmacologic treatment response of these disorders. This is especially true of "eating dysregulation, mood dysregulation, impulsivity and compulsivity, craving for activity and/or exercise. "Studies have shown a relationship between bulimias effect on metabolic rate and caloric intake with thyroid dysfunction. Causes
Biological
As with anorexia nervosa, there is evidence of genetic predispositions contributing to the onset of this eating disorder. Abnormal levels of many hormones, notably serotonin, have been shown to be responsible for some disordered eating behaviors.
In fact, a search for evidence of bulimia nervosa from the 17th to late 19th century revealed that only a quarter of the overeating cases they examined actually vomited after the binges. There was no evidence of deliberate vomiting or an attempt to control weight. 20th century
Globally, bulimia was estimated to affect 3.6 million people in 2015. About 1% of young women have bulimia at a given point in time and about 2% to 3% of women have the condition at some point in their lives. The condition is less common in the developing world. Bulimia is about nine times more likely to occur in women than men. Among women, rates are highest in young adults. Bulimia was named and first described by the British psychiatrist Gerald Russell in 1979.At the turn of the century, bulimia (overeating) was described as a clinical symptom, but rarely in the context of weight control. Purging, however, was seen in anorexic patients and attributed to gastric pain rather than another method of weight control.In 1930, admissions of anorexia nervosa patients to the Mayo Clinic from 1917 to 1929 were compiled. Fifty-five to sixty-five percent of these patients were reported to be voluntarily vomiting to relieve weight anxiety. Records show that purging for weight control continued throughout the mid-1900s. Several case studies from this era reveal patients with the modern description of bulimia nervosa. In 1939, Rahman and Richardson reported that out of their six anorexic patients, one had periods of overeating, and another practiced self-induced vomiting.