In a new report analysis was made of studies on use of e.g. mobile phones and tablets and sleep and tiredness. The report included analysis of 20 cross-sectional studies of children and adolescents aged 6-19 years, in total more than 125,000 subjects. Use of media devices during bedtime gave about doubled risk for inadequate sleep, poor sleep and tiredness daytime. Also if these devices were not actively used an increased risk, although lower, was found for these health problems.
In USA 72 % of children and 89 % of adolescents have access to at least one media device. Most of them use it during bedtime.
Various pathways were discussed for the negative sleep impact: “First, they may negatively influence sleep by directly displacing, delaying, or interrupting sleep time. Second, the content can be psychologically stimulating, and, third, the light emitted from devices affects circadian timing, physiological sleep, and alertness.”
It is remarkable that the authors do not discuss exposure to radiofrequency (RF) fields (electromagnetic radiation) as a contributing factor. Wireless devices such as mobile phones (smartphones) emit RF radiation also when they are not used; updating apps, internet, SMS etc. This passive exposure may have contributed to the sleep disturbances in persons that did not actively use them. The authors seem to have been unwilling to discuss RF radiation. In fact studies on electromagnetic radiation were excluded. Also wireless use of desktops and computers would have been of interest. The authors stated:
“The exclusion criteria were studies of stationary exposures, such as televisions or desktop or personal computers, or studies investigating electromagnetic radiation.”
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