Sleep duration is associated with healthy diet scores and meal patterns: Results from the population-based EpiHealth study

Study Objectives: To investigate relationships between sleep duration and adherence to healthy diets, but also associations with meal patterns, in a large population-based cohort. Methods: Participants (n = 23,829, males and females, aged 45 to 75 years) from the Swedish EpiHealth cohort study were included in a cross-sectional analysis. The participants filled out an extensive Internet-based questionnaire, and also visited a test center for anthropometric measurements and blood sampling. Sleep duration was classified as short (< 6 h/night; n = 1,862), normal (6 to less fewer than 9 h/night; n = 19,907) and long sleep (≥ 9 h/night; n = 858). In addition, a combination variable of sleep duration (short/normal/long) and sleep quality (good/poor) was constructed, giving six categories. Adherence to a healthy diet was assessed using the modified Mediterranean diet (mMED) score and the Healthy Nordic Food Index (HNFI) score based on food groups from a food frequency questionnaire. A regular meal pattern was considered if the participant had breakfast, lunch and dinner on a daily basis. Results: Compared with normal sleepers, short sleepers displayed lower adherence to a healthy diet when using both the mMED score (adjusted odds ratio = 0.70; 95% confidence interval 0.56-0.88) and the HNFI score (0.70; 0.56-0.88). When combining sleep duration and sleep quality, short sleepers with poor sleep quality showed an independent relationship with low adherence to a healthy diet (0.67; 0.52-0.86) compared with normal sleepers with good sleep quality. In addition, both short sleepers (0.71; 0.62-0.82) and long sleepers (0.75; 0.62-0.91) showed low adherence to regular meal patterns, compared with normal sleepers. Furthermore, short sleepers with poor sleep quality had reduced odds of having a regular meal pattern (0.67; 0.57-0.79) as compared with normal sleepers with good sleep quality. Conclusions: Short sleep duration combined with poor sleep quality is associated with low adherence to a healthy diet and regular meal patterns.