According to a 2014 finding of the National Sleep Foundation most 15- to 17-year-olds routinely get no more than seven or fewer hours of sleep, which is a good two hours less than what they should be getting for a healthy life. Further, the study showed that youngsters, who switched off their electronic gadgets before tucking in, enjoyed a better quality of sleep. The finding establishes that there is a clear connection between screen time and sleep. It is not clear, however, whether this connection is somatic (purely physical), psychosomatic (caused by the mind) or the result simply of mass hysteria brought about by digital ubiquity.
Put very simply, the amount of time a child spends on a gadget in his bedroom is equivalent to the amount of lost sleep time. The study showed that children who could access three types of technology in their bedroom slept 45 minutes less than those without. Logically it may be said that older children, given with their more active social life, would spend more time on gadgets than the pre-tweens who were surveyed.
Technology-led delays in bedtime or total sleep time among adolescents has been linked to sleep deprivation, sleep-onset latency (SOL), sleep difficulties, night-time awakenings, and parasomnias.
The biochemical effects of screen aggravate the disturbance caused to sleep.
Circadian (sleep) phase alterations among teenagers are already associated with social demands (early school timings etc) which lead to sleep deprivation. Light also affects the circadian rhythm. Melatonin, the sleep-promoting hormone is suppressed by light, according to recent studies. Indeed statistically significant suppression of melatonin can result from just two hours of such exposure.
Among the factors that play an important role in sleep patterns are the dose, exposure duration, timing and wavelength of light. Short-wavelength light (blue) than mid- (green) or long-wavelength (red) light are particularly harmful to sleep.
Also linked to longer screen time are eating disorders and higher intake of calories as well as consumption of more soft drinks and junk food. All of which leads to based sedentary behavior and obesity weight, particularly when screen time exceeds two hours. A 20-year review of obesity-associated diseases among children aged 6 to 17 conducted by the Centers for Disease Control and Prevention said that that obesity causes sleep apnea among children that leads to sleep deprivation. Sleep deprivation in turn leads to more obesity in a vicious cycle that can effectively be traced back to extensive media use.