Researchers in the United Kingdom have found that the more time babies and toddlers spend with touchscreens, the less sleep they appear to get.

The study, published in Scientific Reports, was based on an online questionnaire administered to 715 families with children aged six months to 36 months.

Parents reported that 75 per cent of their babies and toddlers were looking at touchscreens on devices like iPads and smartphones each day.

The amount of average daily screen time reported ranged from about nearly nine minutes a day for babies aged six to 11 months to 45 minutes a day for toddlers aged 26 to 36 months.

Every additional hour of tablet use was associated with 15.6 minutes less total sleep, according to the researchers’ calculations.

Study author Tim Smith, a psychologist at the University of London, told CTV News Channel Thursday that he was especially surprised by the sheer amount of time children seem to be spending with touchscreens.

“Some of them had quite excessive use of up to two hours -- before they’re old enough to walk, before they’re speaking,” he said.

Smith said it’s too soon to know whether that screen time or its associated loss of sleep will have any long-term effects but that parents may want to limit exposure until more is known.

“The first three years are really important for our behavioural social and brain development,” he said. “Our brain will adapt much more rapidly in those years than it will in the rest of our life.”

The study’s authors suggest four possible reasons why increased screen time may be correlated with less sleep:

  • electronic media may directly displace the time that children have available for sleep
  • the content of the media may elevate psychological and physiological arousal, making it harder to fall asleep
  • the bright blue light from screens may suppress the sleep hormone melatonin
  • heritable traits such as sensation seeking or hyperactivity may lead to both irregular sleep patterns and increased tablet use

The paper points out that previous research has consistently shown time spent with TV, computer and mobile phones is associated with less sleep in adults, but more research on children is needed.