Parents, here’s a wake-up call — those long hours your children spend glued to screens may be quietly harming their hearts and long-term health. A new study published by the American Heart Association has found that excessive screen time among children and teenagers is linked to higher risks of heart and metabolic diseases later in life.
The research, conducted by scientists from the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) at the University of Copenhagen, analyzed data from more than 1,000 children and young adults in Denmark. It found that each additional hour of recreational screen use—whether it was TV, gaming, or time on phones and tablets—was linked to a measurable increase in cardiometabolic risk scores, which indicate potential for high blood pressure, obesity, high cholesterol, and insulin resistance.
Lead author Dr. David Horner explained that while the increase per hour may appear small, it adds up quickly. “A child with three extra hours of screen time a day could have roughly a quarter to half a standard-deviation higher cardiometabolic risk than their peers,” Dr. Horner was quoted as saying by ScienceDaily. “Multiply that across a whole population of children, and you’re looking at a meaningful shift that could carry into adulthood.”
The study revealed that screen time “steals” sleep, worsening the risks even further. Youth who slept fewer hours had a stronger connection between screen use and cardiometabolic problems. Researchers found that about 12 percent of the risk association was mediated through shorter sleep duration, meaning that lack of sleep partly explained why screen time harms heart health.
The Danish team also discovered a distinct metabolic “fingerprint” in frequent screen users — a pattern of blood metabolite changes that may serve as early warning signs of cardiovascular problems later in life. “We found a biological signal — a kind of screen-time fingerprint — suggesting that these lifestyle habits leave measurable traces in the body,” said Dr. Horner.
Supporting these findings, Dr. Amanda Marma Perak, chair of the American Heart Association’s Young Hearts Cardiovascular Disease Prevention Committee, emphasized that managing sleep routines can help curb harmful screen habits. “If cutting back on screen time feels hard, start by moving it earlier and prioritizing longer, better sleep,” she advised. “Parents should model healthy screen behavior — putting devices away during meals or family time teaches children balance.”
Experts also warned that modern lifestyles are pushing cardiometabolic risk earlier than ever. A 2023 American Heart Association report found that only 29 percent of U.S. youth aged 2–19 had ideal cardiometabolic health, showing how early unhealthy patterns are forming.
Though the study was observational and cannot prove direct cause and effect, it provides compelling evidence that recreational screen time is not a harmless pastime. Researchers recommend limiting screen exposure, especially before bedtime, and encouraging outdoor play and physical activity to help safeguard long-term heart and metabolic health.
“This connection starts early,” said Dr. Horner. “Limiting discretionary screen time in childhood and adolescence may be one of the simplest ways to protect lifelong heart health,” he added.
