Too Much Screen Time For Kids Can Lead To Health Issues Decades Later, Study Finds

Excessive screen time in childhood and adolescence has long been linked to developmental delays, but new research published in the Journal of General Internal Medicine finds that screen time can lead to longer-term health issues. In the new study, researchers found that screen time during childhood is a risk factor for obesity, heart disease, and other health disorders in adulthood.

The team followed 7,105 children initially aged 11 to 18 for 24 years from 1994 to 2018 to analyze the effects of screen time on adult health. Participants completed questionnaires at various points throughout the study period, answering questions such as, “How many hours a week do you watch television?” and “How many hours a week do you watch videos?”

The average baseline screen time — in terms of video and television watching — for the children was around 2.9 hours per day, and that time decreased as they aged.

At the end of the study, the researchers found that each additional hour of screen time per day was linked to higher within-person odds of obesity, high waist circumference, and diabetes. Crucially, prior screen time was linked to an increase in BMI at all five check-in points of the study.

The research team credits the sedentary nature of screen time as contributing to the likelihood of developing cardiometabolic health issues in adulthood. “Sedentary behavior displaces physical activity and can lead to increased caloric consumption through avenues such as advertisements that promote high-calorie foods (e.g., fried foods, processed meat, sugar-sweetened beverages), wrote the authors. “Mindless snacking while watching television or videos could be another contributor.” They also added that television advertisements could lead to unhealthy behaviors like smoking.

The team's results corroborate earlier findings that watching television is a risk factor for diabetes, heart disease, and increased risk of death from all causes.

The study did not account for changes in visual media trends over the decades of the study and only asked about time spent watching television or videos, and did not include smartphone or tablet usage. Notably, recreational screen time use is far higher among kids and teens today, with the average at nearly eight hours per day during the pandemic.

Additionally, all screen time data in the new study was self-reported and could therefore be inaccurate.

The team also recognized that using BMI to determine obesity could have skewed results as BMI does not differentiate between lean and fat body mass.

The study is unique, however, in that it followed participants for multiple decades and represented a relatively inclusive population — nearly half were female and 35% were people of color.

“Given the increasing trends of screen time use among adolescents, our findings have important policy and public health implications, particularly as they relate to the development of screen time guidelines and interventions targeted at youth,” wrote the authors. “Screen time guidelines should consider the long-term implications and risk associated with excessive screen time as demonstrated in our study.”