Nutrition Knowledge, Information Sources, and Self-Perceived Ability to Provide Nutrition Counseling Among Medical Students: A Cross-Sectional Study

Background/Objectives: Nutrition is an important component of health promotion and disease prevention, yet medical students may not feel sufficiently prepared to translate nutritional knowledge into patient counseling. This study aimed to assess nutrition knowledge among undergraduate medical students, identify factors associated with knowledge, and examine self-perceived ability to provide nutrition counseling and its associated factors. Methods: A cross-sectional study was conducted among medical students at the University of Santiago de Compostela, Spain, between February and April 2026. Nutrition knowledge and dietary and health-related behaviors were assessed using the refined 46-item version of a validated multidimensional questionnaire. Overall nutrition knowledge was calculated from 29 retained knowledge items. Bivariable analyses, multivariable linear regression, and multivariable logistic regression were performed. Results: A total of 413 students participated. Mean overall nutrition knowledge was 74.9 ± 14.4 points. Scores increased across academic stages, from 70.8 ± 13.6 in years 1–2 to 81.0 ± 13.3 in years 5–6 (p < 0.001). In the adjusted linear model, years 5–6 were associated with higher knowledge scores (β = 6.07; 95% CI 2.43–9.71; p = 0.001), as were reporting the medical curriculum (β = 3.42; 95% CI 0.29–6.54; p = 0.032) and media/social networks (β = 3.33; 95% CI 0.31–6.35; p = 0.031) as information sources. Overall, 37.3% of students considered themselves currently capable of providing nutrition counseling. In the adjusted logistic model, students in years 5–6 had greater odds of reporting current counseling ability (aOR = 3.20; 95% CI 1.63–6.29; p = 0.001), whereas women had lower odds of reporting current self-perceived counseling ability than men (aOR = 0.28; 95% CI 0.16–0.49; p < 0.001), despite no significant gender difference in objective nutrition knowledge. Healthier dietary and health-related behaviors were positively associated with counseling ability (aOR per 10-point increase = 1.63; 95% CI 1.21–2.20; p = 0.001), while overall nutrition knowledge was not independently associated with it (p = 0.437). Conclusions: Students in later academic years had higher nutrition knowledge scores, but greater knowledge did not independently translate into greater self-perceived counseling ability. These findings support longitudinal, practical, and competency-based nutrition education that addresses both knowledge acquisition and counseling preparedness.