Unveiling the relationship between dietary patterns and sleep quality: cross-sectional evidence from university students in Jinan city

Objective Poor sleep quality is common among university students, yet its association with overall dietary patterns remains unclear. This research investigated how dietary patterns relate to poor sleep quality in a population of Chinese university students, using a cross-sectional design. Methods From September to December 2024, we conducted a cross-sectional study at two universities in Jinan, Shandong Province, China. A total of 1,497 students were recruited using cluster sampling. Dietary intake was assessed using a validated Food Frequency Questionnaire (FFQ) covering 12 major food groups. Dietary patterns were derived using principal component analysis (PCA). Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Multivariable logistic regression was used to examine associations between dietary pattern scores and poor sleep quality. Results Three dietary patterns were identified. In fully adjusted models, each 1-SD increase in the PCA3 score was associated with lower odds of poor sleep quality OR = 0.81 (95% CI: 0.70 to 0.93). A significant dose-response trend was observed across PCA3 quintiles ( P for trend = 0.001), and associations were generally consistent across demographic and mental health subgroups. No significant associations were observed for the PCA1 or the PCA2. Conclusion Higher adherence to the PCA3-characterized by higher intakes of fresh fruits, fresh vegetables, and dairy products-was associated with lower odds of poor sleep quality among Chinese university students.