Background/Objectives: Social media use has become ubiquitous, with governmental bodies and researchers expressing a growing concern about its impact on mental health. This review aims to examine the relationship between social media use and disordered eating in individuals aged 18–30. Specifically, we aim to identify specific patterns of use (including addictive use) that are associated with increased risk for disordered eating. Methods: A search was conducted in March 2025 using PubMed and PsycINFO. Keywords were based on social media platforms and eating behaviors. Inclusion criteria were published studies in peer-reviewed journals from 2015–2025, written in English, with participants aged 18–30, whose disordered eating outcomes were assessed using validated measures. Conclusions: 637 articles were screened, with 28 studies meeting the inclusion criteria. Most studies assessed general social media use, without specifying the platform type. The EAT-26 and EDE-Q scales were used in most research to assess disordered eating. Data were narratively synthesized based on the type of social media variables assessed. Our findings demonstrate a complex relationship between social media use and disordered eating, with more consistent associations being found when the type of content (fitspiration and thinspiration) was the independent variable. These findings align with qualitative findings, which highlighted ambivalence in relation to the effect of social media: it is viewed as both a source of support and social comparison. Avenues for future research include longitudinal studies to understand the interaction between individual factors and social media patterns of use, as well as the utilization of platform-generated data on online engagement patterns.