Like precedent disease outbreaks, COVID-19 has immense implications for health challenges. The social restrictions and disruption in daily activities pose a psychological burden for humans worldwide and may be particularly detrimental for individuals with mental disorders. Psychological stressors stemming from the COVID-19 pandemic and resultant stay-at-home orders may exacerbate Eating Disorder(ED)- related triggers and present a challenging environment for individuals with anorexia nervosa, bulimia nervosa, and binge eating disorder. In this research, we aim to comprehend how COVID-19 has affected individuals with eating disorders through a comparative analysis of data obtained from online communities. We developed a tool for extracting information from well-known social media communities such as Reddit. We collected data spanning two years before and after the declaration of the pandemic from the subreddits r/AnorexiaNervosa, r/BingeEatingDisorder, and r/EatingDisorders. The research presents multi-faceted tasks where we analyze the content of each of the subreddits by applying a strategy that combines topic modeling, social network analysis, and time series modeling for a better understanding of these communities on both content and network levels. Through a comparative analysis, we address the discussion topic changes based on users’ content and determine how COVID-19 leads to changes in communication patterns within the communities. Finally, we implement time series models like ARIMA, Prophet, LSTM, and Transformer on daily posts and comments count to forecast users’ activities within the subreddit and establish a performance comparison of these time series models. The findings indicate that both the content of users’ discussions and the level of communication and online support-seeking related to eating disorders on Reddit underwent significant changes during the pandemic.