Gender Differences in Eating Habits, Screen Time, Health-Related Quality of Life and Body Image Perception in Primary and Secondary School Students: A Cross-Sectional Study in Spain

The decline in quality of life in recent decades in Spain and how it is related to health factors highlight the importance of considering health-related quality of life (HRQOL) as a key indicator in the assessment of well-being. Marked by physical, hormonal and social changes, adolescence is a critical period when lifestyle habits are consolidated, including physical activity and diet, which affect HRQOL. There are growing concerns that body image, especially in a context of increased sedentarism and screen use, is associated with low self-esteem and mental health problems. The promotion of healthy habits and a positive body image during this age is essential to improve overall well-being and prevent psychological disorders. This study examines differences in screen time, Mediterranean diet adherence, health-related quality of life and body image self-concept in children and adolescents, considering gender and educational level. A cross-sectional analysis was conducted with 305 students (ages 11–14) from primary and secondary schools. The instruments used to measure the different variables were the KIDMED questionnaire for adherence to the Mediterranean diet, the Screen-time Sedentary Behaviour Questionnaire (SSBQ) for screen time, the KIDSCREEN for health-related quality of life and the Body Size Guides (BSGs) for body image perception. The results showed significant differences by educational stage in screen time, health-related quality of life and body image, with secondary school students reporting higher values. No significant differences were found based on sex. The originality of this study lies in its holistic approach to identify patterns of behaviour and well-being, influenced by sociocultural and demographic factors, and in the detailed analysis of variations by age and gender that affect physical and mental health during critical stages of development. The findings highlight the need for educational strategies to promote healthy lifestyles, involving students, families and their environments, to enhance well-being and self-esteem.