Background: Mental health issues among university students have increased, showing higher levels of anxiety, stress, and depression associated with risky eating behaviors. Objective: Analyze the relationship between eating behaviors and levels of stress, anxiety, and depression in university students. Methods: A cross-sectional study was conducted with 802 students from a public university in southern Chile. Participants completed an online questionnaire that included several instruments. The DASS-21 scale was used to measure levels of depression, anxiety, and stress in Chilean university students, along with a validated survey on eating habits. Additionally, body image was assessed using Stunkard's body silhouette figures. Statistical analysis was performed using SPSS v. 25 software, including descriptive analysis, bivariate chi-square analysis to estimate associations, and simple logistic regression. Results: 54.1% of the students presented malnutrition due to excess, which was significantly associated with mental health symptoms (p<0,050). Not consuming vegetables and the habit of skipping breakfast were correlated with symptoms of depression and anxiety, respectively, while snack consumption was linked to higher levels of stress (p<0,050). Self-perception of body image showed moderate concordance with self-reported body mass index. Conclusions: Our analysis revealed that not consuming vegetables and the habit of skipping breakfast were correlated with higher levels of depression and anxiety, respectively, while snack consumption was linked to higher stress symptoms. Finally, Stunkard's body silhouette test proved to be a valid tool for assessing self-reported body mass index.