Background Dietary intake constitutes a fundamental support in hospitalized patients to reduce morbimortality, risk of complications, and hospital stay. Objective We compared dietary intake, stress, anxiety, and satisfaction with the nutrition service in patients with and without COVID-19; we also analyzed the correlation between the variables mentioned. Methods A cross-sectional, comparative, and correlational study was carried out. A total of 215 patients were selected by non-probability convenience sampling (97 with COVID-19 and 118 without COVID-19). Results Patients with COVID-19 presented a higher percentage of “all the dish served” consumption (63.9%), as well as a higher percentage of “high” anxiety (18.6%) and “very high” satisfaction (28.9%) compared to their counterparts without COVID-19. The stress variable was predominantly moderate in both groups (57.7% vs 55.9%). Statistically significant and indirect correlation was found between satisfaction and stress level (rho = −0.289; p<0.01) in patients without COVID-19; similarly, between intake and stress level (rho =−.254; p<0.05) in patients with COVID-19. Both groups presented a statistically significant and direct correlation between anxiety and stress level (rho =0.432 without COVID-19, rho = 0.525 with COVID-19; p<0.01). Conclusion The findings suggest a multidisciplinary intervention, in which the improvement of mental health in the study population is contemplated and to coadunate the negative effects on the perception of the quality of care of the nutrition service and on dietary intake.