Breakfast skipping, late dinner intake and chronotype (eveningness-morningness) among medical students in Tabuk City, Saudi Arabia.

Introduction: there is an increasing awareness regarding meal timing and chronotype. The present study aimed to assess breakfast skipping, late dinner intake, and chronotype among Saudi medical students. Methods: a cross-sectional study was conducted among 169 clinical phase medical students during the period from January to May 2017. A self-administered questionnaire was used to report the frequency and timing of breakfast and dinner. In addition, the previous cumulative grade average, bedtime, wake-up time, and sleep duration during working days and weekends were reported. The chronotype was calculated from mid-sleep and wakeup time during weekends and sleep dept. The students weight and height were measured to assess the body mass index (BMI). Participants also completed a diary detailing their sleep habits for two weeks before filling out the questionnaire. The chi-square and Pearson's correlation were used for the statistical analysis. Results: out of 169 medical students (48.5% males), their age was 22.90 +/- 1.27 years, 42% were breakfast-skippers, while 49.7% were late dinner consumers. No correlation was found between the previous cumulative grades (GPA), BMI, chronotype, and time lag in wakeup and bedtime between weekdays and weekends (p>0.005). No significant statistical differences between breakfast-skippers and late dinner consumers and their counterparts regarding GPA and chronotype. Conclusion: breakfast skipping and late dinner consumption were prevalent among medical students in Tabuk, Saudi Arabia, future large sample case-control studies to assess the impact of meal timing, and chronotype on academic performance are highly recommended.