Purpose The COVID-19 pandemic has been a leading cause of stress and feelings of loss of control, both of which have been related to eating disorder (ED) pathology onset and deterioration. We aim to estimate the magnitude of changes in the prevalence rates of, and indicators for, ED psychopathology in the face of the COVID-19 pandemic. Method Pre-registered systematic review with frequentist and Bayesian meta-analyses. Searches for eligible studies were performed in PubMed, Web of Science and pre-print servers until January 15 2023. Results Our searches yielded 46 eligible studies reporting on a total of 4,688,559 subjects. These data provide strong evidence indicating increased rates of diagnosed and self-reported ED’s and a concordant increased need for care in the face of the pandemic. ED symptom severity scores in patients were not elevated during the pandemic, except for those related to anorexia nervosa. On average, people in the general population report relatively high levels of emotional and binge eating during the pandemic, although the evidential strength for these associations is only anecdotal to moderate. Moderators of between-study heterogeneity were not detected. Conclusions Altogether, our results suggest that the COVID-19 pandemic is associated with a wide spread negative effect on ED pathology in patient samples and the general population. The development of online prevention and intervention programs for EDs during stressful times like a pandemic is encouraged. A limitation is that the results reported here may be prone to biases, amongst others, self-report bias. Level of evidence: Level I, systematic review and meta-analysis. Preregistration: Prospero [https://www.crd.york.ac.uk/prospero] ID: CRD42022316105.

Objective The COVID-19 pandemic has been a leading cause of stress and feelings of loss of control, both of which have been related to Eating Disorder (ED) pathology onset and symptom deterioration. To estimate the magnitude of changes in the prevalence rates of, and indicators for, ED psychopathology in the face of the COVID-19 pandemic. Method Pre-registered systematic review with frequentist and Bayesian meta-analyses. Searches for eligible studies were performed in PubMed, Web of Science and pre-print servers until March 18 2022. Results Our searches yielded 39 eligible studies on a total of 4.639.947 subjects. Rates of diagnosed and self-reported ED’s and ED symptoms significantly increased in the face of the pandemic. ED symptoms and severity, and emotional and binge eating were reported more often during the pandemic. The need for ED related care increased concordantly. The strength of significant associations was small-to-moderate in most cases. Findings of frequentist and Bayesian meta-analysis converged. Moderators of the substantial between-study heterogeneity were not detected and there was little evidence for the existence of publication bias. Conclusions Altogether, our results suggest that the COVID-19 pandemic is associated with a wide spread negative effect on ED pathology. The development of online prevention and intervention programs for EDs during stressful times like a pandemic is encouraged. A limitation is that results may be prone to biases, amongst others, self-report bias. Preregistration Prospero [https://www.crd.york.ac.uk/prospero] ID: CRD42022316105