Internal Migration, Mealtime Social Disconnection, and Alcohol Use Are Linked to Poor Dietary Habits Among Peruvian Medical Students

Background: Medical students are a vulnerable population with elevated cardiometabolic and mental health risks. Dietary habits are key modifiable behaviors that may mitigate these risks, yet social and contextual determinants such as internal migration, social disconnection, and alcohol use remain underexplored, particularly in middle-income settings. This study examined dietary habits among Peruvian medical students and evaluated the associations of internal migration, mealtime social disconnection, and alcohol consumption with poor habits. Methods: We conducted a cross-sectional study of 223 medical students in Peru. Dietary habits were assessed using a validated nutritional habits questionnaire adapted for the target population (Diet History Questionnaire test, Peruvian adaptation—DHQ-P). The score ranged from 0 to 58, with poor habits defined as <30 based on previous studies and the sample median. Mealtime social disconnection, internal migration, and alcohol use were explored as associated factors. Multivariable Poisson regression models with robust standard errors were used to estimate adjusted prevalence ratios (aPRs), controlling for age, gender, medical school semester, and income. Causal mediation analysis evaluated whether mealtime social disconnection mediated the association between internal migration and dietary habits. Sensitivity to unmeasured confounding was assessed using E-values. Results: Poor dietary habits affected approximately 47% of students. Internal migrants comprised 44% of the sample, 35.8% reported eating all meals alone, and 67% reported alcohol use more than once per month. Each additional meal eaten alone was associated with a higher prevalence of poor habits (aPR 1.17, 95% CI 1.02–1.38), and eating all meals alone also increased the prevalence (aPR 1.14, 95% CI 1.02–1.28). Similarly, recent internal migration (aPR 1.38, 95% CI 1.04–1.83), lifetime internal migration (aPR = 1.85; 95% CI, 1.16–2.95), and higher frequency of migration (aPR = 1.17; 95% CI, 1.01–2.38) were linked to poor dietary habits. Moreover, alcohol consumption (aPR 2.06, 95% CI 1.60–2.67) was independently associated with poor dietary habits. Mealtime social disconnection partially mediated 19% of the migration–dietary habits association (p = 0.03). Associations were robust to unmeasured confounding (E-values 1.34–2.23). Conclusions: Poor dietary habits are highly prevalent among Peruvian medical students and are independently associated with internal migration, mealtime social disconnection, and alcohol use. Addressing social eating contexts and migration-related vulnerabilities may offer novel opportunities to improve dietary behaviors among future physicians.