Eating disorder portion of the vulnerability to develop eating disorders can be inherited, and there is evidence to show that there is a genetic locus that shows susceptibility for developing anorexia nervosa. About 60% of eating disorder cases are attributable to biological and genetic components. Other cases are due to external reasons or developmental problems. There are also other neurobiological factors at play tied to emotional reactivity and impulsivity that could lead to binging and purging behaviors. Epigenetics: Epigenetic mechanisms are means by which environmental effects alter gene expression via methods such as DNA methylation; these are independent of and do not
Other specified feeding or eating disorder can be considered eating disorders include atypical AN, BN (of low frequency and/or limited duration), BED (of low frequency and/or limited duration), purging disorder, and NES. Of note, OSFED is not limited to these five examples, and can include individuals with heterogeneous eating disorder presentations (i.e., OSFED-other). Another term, Unspecified Feeding or Eating Disorder (UFED), is used to describe individuals for whom full diagnostic criteria are not met but the reason remains unspecified or the clinician does not have adequate information to make a more definitive diagnosis. Few studies to date have examined OSFED prevalence. The largest community study is