Study says too much screen time may harm kids’ hearts: Here’s how to keep them safe

Is an evening of gaming or endless scrolling really harmless downtime for kids? A new study suggests it might be taking a hidden toll on their heart health. Researchers have found that long hours in front of screens, whether on phones, TVs, or consoles, are linked with higher risks of cardiometabolic problems such as high blood pressure, insulin resistance, and cholesterol issues.



The findings, published in the Journal of the American Heart Association, come at a time when concerns are already rising. In 2023, the American Heart Association reported that “cardiometabolic risk is accruing at younger and younger ages,” noting that only 29% of U.S. children and teens between 2 and 19 had healthy cardiometabolic profiles, based on federal survey data.

What the study found

The new analysis, which drew from more than 1,000 participants in two Danish studies, found a clear link between recreational screen use and increased cardiovascular and metabolic risks in young people. Using data from children and teenagers enrolled in the Copenhagen Prospective Studies on Asthma in Childhood, researchers measured how extra hours of screen time affected cardiometabolic scores.



“Limiting discretionary screen time in childhood and adolescence may protect long-term heart and metabolic health,” said lead author David Horner, M.D., Ph.D., of the University of Copenhagen.



The results were striking. Each additional hour of screen time raised cardiometabolic scores by 0.08 standard deviations in 10-year-olds and 0.13 in 18-year-olds. As Horner explained: “This means a child with three extra hours of screen time a day would have roughly a quarter to half a standard-deviation higher risk than their peers.”



The study also showed that sleep habits matter. Kids who stayed up late or slept fewer hours were more vulnerable—showing significantly higher risks compared to peers who logged enough rest.

What parents can do

Cutting back on screen time is easier said than done, but experts say small shifts can go a long way. Here are five ways families can start:

Set screen-free hours at home

Having a few “no screen” times—like mealtimes or the hour before bed—helps kids step away from constant stimulation and build healthier routines.

Encourage outdoor activities

Organizing evening walks, sports, or even casual outdoor play reduces sedentary time and naturally keeps screens at bay. Kids are more likely to unplug when movement feels fun.

Create device-free bedrooms

Screens in bedrooms can delay sleep and make late-night scrolling harder to resist. Keeping devices out of sleeping spaces helps ensure better rest.

Lead by example

Parents who also unplug—whether reading a book, cooking, or exercising—set a powerful example. Kids mirror habits more than rules.

Replace screens with engaging hobbies

Music, art, or puzzles give children something equally stimulating without the health risks tied to endless screen time. Reframing free time as an opportunity, not just a break from screens, helps new habits stick.