Chronotype and its Association With Weight Status and Dietary Patterns Among Tunisian Female University Students

Abstract

Circadian clocks regulate physiological rhythms based on light, food intake, and fasting. Disruptions to these clocks are associated with health problems. Chronotype, reflecting individual circadian preferences, is influenced by sleep and eating habits, especially in students. This study aimed to determine the chronotype of Tunisian female university students and examine its relationship with weight status, nutritional status, and eating disorders. A descriptive cross-sectional study was conducted with 80 female university students. Participants completed questionnaires assessing general characteristics, physical activity, sleep quality (Pittsburgh Sleep Quality Index), chronotype (Morning–Evening Questionnaire), eating habits and disorders (Three-Factor Eating Questionnaire), and dietary intake (Nutrilog software). Body composition was measured using bioelectrical impedance analysis. The mean age was 20.85 ± 0.98 years. Chronotype distribution was 22.5% morning, 47.5% intermediate, and 30% evening. Evening chronotypes had significantly higher BMI (27.01 ± 5.26 kg/m²) and body fat percentage (27 ± 4.25%) (P < .001). They showed delayed meal timing, lower physical activity (P = .02), less regular breakfast consumption (P < .001), longer meal durations (P = .03), and higher fastfood intake (P < .001). Additionally, they exhibited increased eating disorders, sleep disturbances (P = .003), and excessive energy, carbohydrate, lipid, and protein intake (P < .01). Assessing chronotype in students may help detect early health risks. Larger studies and biological assessments are recommended.

Plain Language Summary

This study explored how the daily biological rhythm, known as chronotype, is linked to health and eating habits among Tunisian female university students. A chronotype describes whether a person naturally prefers to be active in the morning, in the evening, or somewhere in between. These preferences can affect sleep, diet, and overall health.

We surveyed 80 female students and collected information about their sleep quality, physical activity, eating habits, and daily food intake. We also measured their weight and body composition. The results showed that 30% of the students had an evening chronotype, meaning they preferred going to bed and waking up later.

Evening-type students had a higher body mass index and more body fat compared with morning-type students. They also tended to delay their meals, skip breakfast more often, and eat fast food more frequently. Their levels of physical activity were lower, and they experienced more sleep problems and signs of disordered eating. In addition, they consumed higher amounts of energy, carbohydrates, fats, and proteins.

These findings suggest that chronotype may play an important role in students’ health and daily behaviors. Identifying chronotype early could help guide personalized nutritional advice and promote healthier routines.