Rates of overweight and obesity among children continue to rise at an alarming pace and, what is worse, with no signs of stopping. For example, in Western countries, the prevalence of obesity in children and adolescents (between 2 and 19 years of age) has risen from 17% and 16% in 1980 to 24% and 23% today in boys and girls, respectively (1). Not surprisingly, the World Health Organization (2) considers childhood obesity one of the most serious public health problems of the twenty-first century, reaching epidemic proportions worldwide. In addition, childhood obesity is not a problem that is reflected only at this stage of life, but the negative consequences inherent in excess weight during childhood and adolescence will have a great impact on future health. In this sense, overweight and obesity during the early stages of life are associated with an increased risk of cancer, cardiovascular and metabolic diseases in adulthood. Therefore, having obesity during childhood and adolescence is a risk factor for future morbidity.
A poor diet and a lifestyle based on sedentary habits are the main reasons for this global childhood obesity epidemic. The use of new technologies (mainly tablets and smartphones) is increasingly widespread among young people, with the consequent increase in the time they spend sitting in front of a mobile screen. Thus, the Anibes Study that analysed the sedentary habits of Spanish children and adolescents between 9 and 17 years old, coordinated by the Spanish Nutrition Foundation (http://www.fen.org.es/), concluded that 49% of participants spent more than two hours a day from Monday to Friday in front of a screen, while the percentage rose to 84% on weekends (3).
On the other hand, a recent systematic review with meta-analysis evaluated the effect of sedentary habits (watching television, using a mobile screen or using the computer) on various indicators of cardiometabolic health, finding that there is strong evidence of a positive association with overweight and obesity and an inverse association with physical fitness and HDL cholesterol (4). When analyzing the different sedentary habits individually, they found that spending time in front of a mobile screen was associated with a higher body mass index and watching television with a higher rate of overweight/obesity, while computer use was not related to any of the indicators analyzed.
In another meta-analytic study that included more than 106.000 children, the authors concluded that there is a dose-response relationship between sitting watching television and excess weight in childhood, i.e., the longer they spend in front of the television, the greater the risk of obesity, increasing the risk by up to 13% for each hour a day they spend watching television (5).
However, the excessive use of mobile screens among children leads not only to them moving less than recommended with the consequent risk of weight gain, but can also affect the quality and quantity of sleep. Sleep, which plays a fundamental role in the health and development of children, especially in the first years of life, has been disrupted by the arrival of mobile devices such as smartphones or tablets and it is now common to see children use these devices in their own bed before going to sleep. thereby harming their rest. The data obtained in the Gasol Foundation's (https://www.gasolfoundation.org/es/estudio-pasos/) PASOS study show that 41% of Spanish children and adolescents do not comply with the recommendations for hours of sleep during the week, increasing the percentage to 48% when the weekend arrives. A recent systematic review analyzed the association between the time spent on mobile screens (computers, mobile phones and/or tablets) and different variables related to the quantity and quality of sleep in children and adolescents between 5 and 17 years of age (6). Most studies (75-94%) found a significant association between the use of these screens and a shorter duration and quality of sleep. For example, children and adolescents who used the internet before bed slept 51 minutes less, those who played video games 28 minutes less, and those who looked at their mobile phones before going to sleep saw their sleep time reduced by 21-45 minutes.
In short, we observe how excess weight is not only problematic in adulthood, showing the relevance of avoiding overweight from the earliest age. To this end, it seems evident that there is a need to avoid sedentary behaviours, including the excessive use of devices with mobile screens (computers, tablets, smartphones), which will also affect their sleep and rest, putting their physical, emotional and intellectual performance at risk. Finally, we must be aware that the time children spend using mobile screens is time taken away from developing motor, social or cognitive skills.
REFERENCES:
- Ng M, Fleming T, Robinson M, Thomson B, Graetz N, Margono C, et al. (2014). Global, regional, and national prevalence of overweight and obesity in children and adults during 1980–2013: a systematic analysis for the global burden of disease study 2013. Lancet, 384,766–781.
- World Health Organization (2018). Childhood overweight and obesity. Retrieved February 12, 2020, https://www.who.int/dietphysicalactivity/childhood/es/
- Mielgo-Ayuso J, Aparicio-Ugarriza R, Castillo A, Ruiz E, Avila JM, Aranceta-Bartrina J, et al. (2017). Sedentary behavior among Spanish children and adolescents: findings from the ANIBES study. BMC Public Health, 17, 94.
- van Ekris E, Altenburg TM, Singh AS, Proper KI, Heymans MW, & Chinapaw MJ. (2016). An evidence‐update on the prospective relationship between childhood sedentary behaviour and biomedical health indicators: a systematic review and meta‐analysis. Obesity reviews, 17, 833-849.
- Zhang G, Wu L, Zhou L, Lu W, & Mao C. (2016). Television watching and risk of childhood obesity: a meta-analysis. The European Journal of Public Health, 26, 13-18.
- Hale L, & Guan S. (2015). Screen time and sleep among school-aged children and adolescents: a systematic literature review. Sleep Medicine Reviews, 21, 50-58.
AUTHOR
Javier S. Morales
Lecturer and researcher in pediatric oncology and exercise.
Web: www.fissac.com
