Children are beginning to use screen-based devices more and more at an early age, and are spending more and more time in front of them. This behavior is associated with unhealthy dietary patterns, poor sleep quality, an increased risk of cardiovascular disease, and a higher rate of obesity in children. It also has negative consequences for mental health, especially attention deficit problems in the youngest, in adolescents in whom social networks have a special role. There is information available that indicates that the time spent on screens is negatively associated with increased adiposity, changes in sleep hours, psychomotor difficulties, decreased quality of life, self-esteem problems, poor academic performance and deterioration in social skills, higher degree of anxiety and depression. On the contrary, the regular practice of physical activity is associated with greater well-being and a better state of mental health. In parallel, the rate of child and adolescent obesity has increased, in which sedentary lifestyle plays a relevant role. Low levels of physical activity, along with prolonged leisure time in front of a screen and 7 the presence of obesity are associated with worse scores on well-being scales in children, although the number of studies that correlate all these variables is scarce. Scientific societies have clearly indicated in recent years the recommendations for the use (consumption) of screen time based on age: thus, the American Academy of Pediatrics recommends avoiding the use of screens in children under 18 months, except for family gatherings (video-chatting), between 18 and 24 months, parents must choose very high quality programs and be with the children explaining the contents, between 2 and 5 years the limit must be 1 hour a day and always in the company of the children and above that age its use in limited periods and provided that it is guaranteed that they do not replace sleep, play or physical activity or other actions essential for health. It also recommends having times together free of devices, such as meal times and spaces without screens, such as the bedroom.