Table 4.

Reports dealing with environment and their major finding

Domains	Reference	Highlighted
Red flags/screening Environment Neurilogical patways	McAdams CJ, 2020 [18]	Self-esteem and socializing problems are associated with ED symptoms during adolescence. Social stressors often concur with ED symptom onset. Common stressors are bullying about shape/weight/appearance. In Fijian adolescents, social pressures from a changing society correlate to body size concerns and ED. Adolescents with AN presented reduced activation in the superior temporal sulcus. Adolescents who recovered from AN had no whole-brain differences, and less activation in the precuneus one year later. Study in adolescents with AN showed reduced processing in the social condition in the medial prefrontal cortex and less activation in this region at baseline was associated with worse outcomes a year later. In adolescents with AN, dorsolateral prefrontal cortex activation at baseline was related to increased amygdala.
Red flags/screening Environment	Herpertz-Dahlmann B, 2021 [28]	Children had a significantly shorter illness duration and a higher BMI percentile at admission than adolescents in case of regular pediatric health check-up for 12–15 year olds in Germany since 1998. The effects of appearance-focused gaming vs. Girls exposed to appearance- focused gaming had higher body dissatisfaction.
Genetic Environment	Steiger H, 2020 [33]	In a study involving 3,495 people with AN, a locus on chromosome 12 had been found associated with AN. Swedish hospital records showed that children having a parent with an autoimmune disorder are likely to develop an ED. As for epigenetic origins, the degree of in utero stress exposure correlates to ED. In AN, studies have reported altered methylation of genes regulating expression of alpha-synuclein, dopamine, oxytocin, histone deacetylase and leptin (hormone linked to nutritional status and the immune response). Obstetric insults, gestational stress, childhood trauma, familial conflict, adult victimization experiences, social contests may play a role in AN.
Environment	Spettigue W, 2023 [38]	The COVID-19 pandemic has been associated with an increase in the incidence of eating disorders and of its severity in clinical manifestations.
Environment	Vyver E, 2021 [39]	COVID-19 pandemic restrictions have been identified as having contributed to the increased incidence of eating disorders.
Environment	Parpia R, 2023 [40]	COVID 19 pandemic impacted on adolescents ED.
Environment	Gorgas DL, 2024 [41]	A higher number of new diagnoses of and hospitalizations for AN or atypical AN in children and adolescents during the first wave of the COVID-19 pandemic was seen in Canada.
Environment	Bryant E, 2022 [42]	Neuropsychiatric problems including anxiety, anger, bullying, sexual abuse and bereavement were linked to ED.
Environment	Giles EM, 2022 [43]	A family history of eating disorders in in early adolescence has a more substantial impact than in older adolescents: girls younger than 14 years whose mothers had a ED had a 3 times higher risk to start purging than the peers.
Environment	Mento C, 2021 [44]	Pro-ana websites and a problematic use of social networks were linked to body and self-perception. Offering feedback on their aspect and advice on how to lose weight. Publications containing emotional words linked to stigma, the specific content of anorexia, and very correlational content generally trigger negative feedback from other members of the pro-anorexia community.