Effect of Screen Time, Sedentary Behavior, and Sleep Disruption on Obesity and Metabolic Syndrome in Adolescents and Young Adults: A Systematic Review

Background: The prevalence rates of overweight and obesity are witnessing a significant rising trend among adolescents and young adults. One in five children is considered overweight, with an overall prevalence of obesity recorded at 8.5%. Additionally, about 25% of the world’s population is diagnosed with metabolic syndrome. Young adults and adolescents are at higher risk of developing metabolic syndromes, making them susceptible to developing cardiovascular diseases. Sedentary behavior increases the risk of mortality, cardiovascular diseases, diabetes mellitus, hypertension, and metabolic syndrome. This systematic review aims to evaluate the association between screen time, sedentary behavior, and sleep disruption with obesity and metabolic syndrome among adolescents and young adults.

Methodology: This systematic review was conducted according to the PRISMA checklist. Major outcomes included the associations between screen time, smartphone use, sleep duration, sedentary behavior, and physical activity with obesity-related and cardiometabolic outcomes across children, adolescents, and young adults. A comprehensive search was conducted using a combination of electronic databases, including PubMed, Scopus, and Web of Science.

Results: The review included 14 observational studies, published between 2010 and 2025. The findings of the included studies demonstrated that higher screen time, sedentary behavior, poor sleep duration, and lower physical activity levels were associated with adverse obesity-related and cardiometabolic outcomes. Multiple studies reported that prolonged screen exposure was significantly associated with higher BMI, abdominal obesity, metabolic syndrome, central adiposity, elevated triglycerides, and reduced cardiorespiratory fitness. Short sleep duration was associated with higher obesity risk, increased insulin resistance, and elevated fasting insulin levels. Physical activity demonstrated a generally protective association against obesity and metabolic abnormalities.

Conclusion: Modifiable lifestyle-related habits such as excessive screen time, sedentary behavior, and inadequate sleep duration are associated with adverse obesity and cardiometabolic outcomes among adolescents and young adults. Therefore, reducing recreational screen exposure, improving sleep hygiene, and promoting regular physical activity should represent important public health priorities.