Eating disorders in twins: a scoping review

Evidence suggests that eating disorders (EDs) are multifactorial, with a complex interplay between genetics and environment. Twin studies have indicated a significant genetic contribution, but non-shared environmental factors also contribute to the variability in their etiology. A scoping review was conducted, finding 32 articles from different databases (PUBMED, EMBASE, and BVS) on twins, with the aim of reviewing the literature that includes information on this interaction in the onset and persistence of ED.The findings revealed that the manifestation of EDs emerges from the interplay between genetic predispositions and environmental influences. Psychosocial factors such as child abuse, family environment, peer pressure, and exposure to sociocultural dynamics that idealize thinness influence the risk of development. Moreover, adverse environmental conditions increase the risk in individuals with genetic predispositions. However, the current literature on EDs in twin populations requires further depth. Most studies focus on underrepresented samples, so research on more diverse cohorts is needed to understand the dynamics of ED diagnosis more precisely. In conclusion, EDs are the product of a complex interplay between genetics and environment. Further research is needed to unravel these dynamics and develop more effective prevention and treatment strategies.