More than two hours of screen time per day is associated with a twofold increase in the likelihood of meeting criteria for possible ADHD in childhood

Children who spend two or more hours a day in front of screens have a 2.16-fold higher relative risk of meeting the screening criteria for a possible attention-deficit/hyperactivity disorder (ADHD) than those who spend less than one hour a day. Similarly, higher consumption of ultra-processed foods is associated with lower scores on the dimensions of hyperactivity, peer relationships, prosocial behavior, and inattention.

These are the main conclusions of the report “ report per diem expenses , Screens, and Symptoms of ADHD in Childhood: Results from the project SENDO Study,” prepared by the group of research at the University of Navarra with the support of Fundación Mapfre. The study is part of the framework of theproject SENDO Study, a prospective pediatric cohort (a group of children monitored over a period of time) that examines how different lifestyle factors relate to children’s health. In this particular analysis, the researchers have focused specifically on diet and screen exhibition , and their relationship to psycho-emotional and behavioral health, as well as symptoms of ADHD, a disorder that already affects between 5 and 7% of children in Spain.

“ADHD has a complex origin involving genetic and neurobiological factors, as well as certain habits that are part of the environment in which childhood unfolds. In this study, we analyzed whether potentially modifiable factors, such as diet or screen exhibition , are associated with a higher likelihood of meeting the screening criteria for possible ADHD,” notes Dr. Nerea Martín Calvo, a researcher at the Institute of Nutrition and Health, a pediatric specialist, and a professor at thedepartment of the Preventive Medicine and Public Health at the University of Navarra. Since this is an observational study, these results do not allow for the establishment of a causal relationship; however, as the specialist points out, having prospectiv programs of study s like this one is important because “it allows us to advance in the knowledge of a relationship that still requires further research and to observe these habits before subsequently evaluating symptoms.”

“The significance of these findings lies in the fact that, for example, diet and screen exhibition are areas where families can take action. promote Healthy habits—such as prioritizing a diet based on fresh foods and limiting time spent in front of electronic devices—can be part of a comprehensive approach to promote children’s health and well-being,” notes Eva Arranz, a physician at Fundación Mapfre.

Prospective methodology

ADHD is one of the most common neurodevelopmental disorders in childhood, and its symptoms range from attention difficulties (inattention) to hyperactivity and impulsivity, which can affect various areas of children’s lives, such as learning, daily functioning, and social relationships. To date, a significant portion of the evidence available has come from cross- programs of study , in which habits and symptoms are assessed simultaneously. This makes it difficult to determine which occurs first and, therefore, to study the temporal sequence between habits and subsequent indicators of psychoemotional health.

The main feature of this work is precisely its prospective design . In this analysis, habits related to diet and screen time were recorded approximately two years before the final assessment of behavioral indicators and ADHD symptoms. In this way, researchers can study the temporal sequence between these habits and subsequent indicators of psychoemotional health and assess whether certain exposures precede the differences observed later. However, because this is an observational study, it does not allow us to conclude that these habits are the cause of the symptoms or of ADHD.

The study analyzed 568 children, who were between the ages of 4 and 5 at the start of the study. Information on diet, physical activity, sedentary behavior, sleep, and other health-related aspects was collected through questionnaires completed by the parents. To evaluate these results, the researchers used two complementary tools. First, the Strengths and Difficulties Questionnaire (SDQ), a 25- questionnaire designed to assess five dimensions of children’s behavior and emotional and social well-being: emotional symptoms, conduct problems, hyperactivity, peer relationships, and prosocial behavior (positive behaviors in interactions with others, such as helping, cooperating, or showing consideration toward others). On the other hand, the DuPaul ADHD Scale was used, which consists of 18 items and focuses specifically on two groups of symptoms related to this disorder: inattention and hyperactivity/impulsivity.

Both tools make it possible to quantify the presence and severity of certain symptoms and to conduct a screening, but they do not replace a clinical evaluation , nor do they, on their own, allow for a definitive diagnosis of ADHD.

Two hours of screen time per day doubles the risk of ADHD

The results showed that 10.9% of the participants met the criteria for “possible ADHD” according to the Du Paul scale. “This classification does not mean that these children have been diagnosed with ADHD. It is a screening- tool t that allows us to identify those who exhibit more symptoms and who, therefore, may require a more comprehensive clinical evaluation ,” explains Dr. Martín-Calvo.

In the “ group ” study analyzed, 61% of children spend less than one hour a day in front of screens, while 39% spend one hour or more a day in front of them. With regard to different levels of exhibition, the researchers observed that spending between one and two hours a day is associated with a relative risk of 1.22 of meeting the criteria for possible ADHD, while for children who spend two hours or more, the relative risk rises to 2.16. In other words, children who spend two hours or more per day in front of screens are twice as likely to meet the criteria for possible ADHD.

The higher the consumption of ultra-processed foods, the worse the indicators