Researchers looked at how diet, sleep, physical activity, and television viewing were related to school performance, while taking into account demographic factors and neurodevelopmental disorders.
Research: Independent and combined associations of lifestyle behaviors on academic achievement in adolescents. Image credit: Pixel-Shot / Shutterstock
In a recent study published online as a “press article” in the journal scientific reportA group of Spanish researchers investigated the independent and combined associations between physical activity, sleep, diet, television viewing, and academic performance in adolescents, taking into account demographic factors and neurodevelopmental disorders (NDs).
background
Is it possible that daily habits such as eating well, getting enough sleep, and limiting television viewing have a bearing on student performance?Adolescence is a critical period for an individual’s physical, social, and mental development, and a healthy lifestyle supports overall well-being.
Academic performance is associated with physical activity, adequate sleep, healthy eating, and less screen time. The individual and combined contributions of these lifestyle behaviors are still not well understood, especially when considering neurodevelopmental disorders, and further research is needed to better understand how multiple lifestyle behaviors collectively relate to educational outcomes in adolescents.
About research
Researchers analyzed data from the INSchool cohort, an ongoing research program investigating mental health and learning disabilities in school-age children in Catalonia, Spain. Data was collected from 974 eighth graders at 22 schools between September 2018 and June 2019.
Information regarding students’ sociodemographic background, lifestyle behaviors, mental health test results, sleep duration, diet, and television viewing was obtained from a parent questionnaire, and adolescents reported their physical activity using the Physical Activity Questionnaire for Adolescents (PAQ-A).
Dietary quality was assessed using the Mediterranean Diet Quality Index (KIDMED) questionnaire, and sleep duration was assessed with specific items of the Childhood Sleep Disorders Scale (SDSC). Academic performance was obtained from official school records and included first language, foreign language, and mathematics performance.
First language performance was calculated by averaging the performance in Catalan and Spanish. Students who tested positive for emotional or behavioral problems and who consented underwent a clinical interview with their parents to determine whether they met diagnostic criteria for attention-deficit/hyperactivity disorder (ADHD) and specific learning disability (SLD).
The relationships between various lifestyle factors and academic achievement were assessed using mixed-effects ordinal logistic regression models, adjusting for gender, ethnicity, and socio-economic status (SES) and accounting for within-school clustering.
The fully adjusted model also considered all lifestyle behaviors simultaneously. Lifestyle adherence was also assessed by counting the total number of recommended healthy behaviors achieved by each participant.
Research results
The study involved 974 eighth graders (49.1% male, 50.9% female) with an average age of 13 years. A total of 26.9% of the sample had at least one ND, including ADHD, SLD, or both.
Adolescents with ND generally had lower performance in native language, foreign language, and mathematics than other adolescents. They were also less likely to practice healthy lifestyle habits, more likely to not eat three meals a day, and spent more time watching television. However, no statistically significant differences were detected between youth with and without ND regarding physical activity, sleep duration, or adherence to Mediterranean diet recommendations.
A high-level analysis showed that students who consistently ate three meals a day, followed a Mediterranean diet, and watched less than two hours of television a day were more likely to earn higher grades than their peers in all subjects.
Getting enough sleep, at least eight hours a night, also led to better math performance. However, meeting physical activity recommendations was not significantly associated with academic performance. Separate analyzes also showed that gender, ethnicity, SES, ADHD, and SLD, along with lifestyle factors, were associated with academic performance.
After adjusting for gender, ethnicity, SES, ADHD, and SLD and considering all lifestyle behaviors simultaneously, we found that several lifestyle behaviors were still independently associated with academic performance.
Adolescents who consistently ate three meals a day were significantly more likely to achieve higher grades in first and foreign language subjects.
Limiting television viewing to less than two hours a day remains associated with foreign language and math achievement, while a Mediterranean diet and eight or more hours of sleep continue to be positively associated with math success. However, physical activity was not independently associated with academic performance in either crude or adjusted analyses. Higher SES and the absence of ADHD and SLD remained associated with better performance in all subjects.
Regarding gender differences, women performed better than men in language subjects, and participants classified as native Spanish speakers performed better in first language and math than participants classified as foreign-born. The foreign-born category included students whose native language was not Spanish or who had at least one parent born abroad.
Cumulative analyzes showed a consistent association between meeting healthier lifestyle recommendations and improved academic performance in all three subjects.
Young people who met four or five healthy lifestyle recommendations were significantly more likely to achieve high grades in first language subjects, foreign language, and math than those who met only zero or one recommendation.
Additionally, students who met two or three of the recommendations were more likely to improve their foreign language performance compared to students who reported the lowest levels of healthy lifestyle adherence.
conclusion
The results showed that healthy lifestyle behaviors, particularly maintaining a Mediterranean diet, eating three regular meals a day, getting enough sleep, and limiting television viewing, were independently associated with better academic performance among adolescents, even after accounting for gender, ethnicity, SES, ADHD, SLD, and other lifestyle behaviors.
Greater adherence to lifestyle recommendations was also associated with better performance in all three academic outcomes, but the study did not prove that behaviors caused these differences or that their combined effects were greater than their individual associations. These results support the idea of evaluating multicomponent school health programs aimed at promoting healthy behaviors in youth.
However, a cross-sectional design means that the direction of causality or association cannot be determined. Additionally, the findings may have limited applicability outside central Catalonia because parents and adolescents reported lifestyle behaviors, measurements were collected at different times, and screen time was limited to watching TV rather than smartphones, computers, video games, and social media.
Because the researchers used a complete case analysis, the number of participants varied for each measure due to missing data. There remains the possibility of residual confounding by factors such as intelligence, treatment status, and other psychiatric disorders.
Reference magazines:
- Prat, R., Pagerols, M., Pagespetit, E., Puig-Ribera, A., Martín, AC, Autet, A., Casas, M., and Bosch, R. (2026). Independent and combined associations of lifestyle behaviors with adolescents’ academic performance. Scientific report. Doi: https://doi.org/10.1038/s41598-026-63038-5
