Does your toddler use a smartphone? While a little bit of screen time might seem harmless, a new survey shows that it could be having a negative impact on their sleep.

It is estimated that children lose 16 minutes of sleep for every hour they spend using a touchscreen. With young children using these devices for an average of 25 minutes per day, they are losing around six minutes of sleep every day, which adds up to 42 minutes over the course of a week. If your child spends an hour using such devices each day, he or she could be losing nearly two hours of sleep a week!

A recent survey carried out in the UK found that three-fourths of toddlers between six months and three years of age use a touchscreen daily. Slightly more than half of those aged six to 11 months use a device daily, but this figure rises to 92 percent among those between the ages of 25 and 36 months.

The use of smartphones and other digital devices is also causing an epidemic of nearsightedness, or myopia, in children. Just a quarter of those aged 12 to 54 were nearsighted in the early 1970s; that figure had grown to more than 41 percent by the 2000s.