Disordered eating (DE) significantly affects both physical and mental health, contributing to morbidity, mortality, and considerable global healthcare costs. This cross-sectional study assessed the prevalence of high-risk DE and examined its associations with body composition, behavioural factors, diet quality, and perceived stress among university students in the United Arab Emirates. A total of 911 students were recruited using non-probability quota sampling (50.49% female). Body composition was measured using a TANITA BC-420MA body composition monitor. Usual dietary intake was assessed via a validated 65-item food frequency questionnaire. DE risk was assessed using the Eating Attitudes Test (EAT-26) and perceived stress using the PSS-10. Analysis included linear regression and independent-samples t-test (p < 0.05). High-risk DE (EAT-26 ≥ 20) prevalence was 30.3%. High-risk DE was significantly associated with higher body fat percentage (β = 0.121, p < 0.001), fat mass (β = 0.148, p < 0.001), fat-free mass (β = 0.079, p = 0.017), lean mass (β = 0.08, p = 0.016), total body water (β = 0.084, p = 0.011), and lower total body water percentage (β = −0.131, p < 0.001). High-risk students also reported higher intakes of fibre (β = 0.12, p = 0.018), beta-carotene (β = 0.14, p = 0.025), vitamin A (β = 0.13, p = 0.034), B12 (β = 0.15, p = 0.043), folate (β = 0.16, p = 0.006), and vitamin D (β = 0.16, p = 0.036). Compared with the low-risk group, high-risk DE was associated with higher adiposity markers and slightly higher perceived stress, and differed in selected nutrient intakes; sociodemographic characteristics were largely similar between groups except for smoking status. These findings support the implementation of targeted prevention strategies, including nutrition education, routine screening, and culturally tailored programmes, for young adults in the UAE.