Limiting a kid's screen time can help them avoid heart disease in the future. According to the American Heart Association, ""Screen time is associated with being overweight and obese which is associated with high cholesterol and high blood pressure." Once those heart disease-causing factors are in play during childhood, they can follow the person into adulthood. On average, kids 8-18 are spending seven hours a day on connected devices like smart phones, tablets and video games. The American Heart Association suggests cutting that time down to 1 to 2 hours a day for children and teens.