In life, it’s nearly always possible to have too much of a good thing, and moderation is usually the right common-sense prescription (no matter what the advertisers say). Screen time is no exception. But how much is too much? That’s the question many parents are asking…

There’s no doubt that a little bit of time watching TV, working on a computer, playing video games or using a tablet or smartphone can be useful. However, it’s also become increasingly clear that long, uninterrupted periods of screen time can cause real problems. This can be a result of the screen-watching activity itself as well as what’s NOT happening while an individual is focused on the screen. While there’s growing evidence that both adults and children are at risk, the rest of this article will focus on kids and what their parents need to know.

Most young children aren’t very good at moderating their behavior or setting their own limits. This means that it’s ultimately an adult’s responsibility to do it for them until they can exercise their own good judgment. And this is true EVEN THOUGH IT TAKES TIME AND EFFORT FROM THE ADULT AND IS OFTEN INCONVENIENT. As tempting as it may be to use devices with screens as electronic “babysitters” to free up your own time, being a parent or caregiver means keeping the child’s needs in mind, too.

Following is a brief summary of the most-widely circulated guidelines for children’s screen time (entertainment-oriented use of electronics), based on recommendations made by the American Academy of Pediatrics.

Under 2 years—No screen time

2–5 years—One hour of preschool TV, but no computer time

5–8 years—One hour

Over 8 years—Two hours

The first couple of years are particularly critical for a child. This is the time when a baby’s brain goes through the most rapid growth and development. Children need to explore and to engage with their broader environment. When these opportunities are limited or “crowded out” in favor of engaging with electronic devices, their cognitive and social development may be altered in negative ways we don’t yet understand. At the same time, researchers have not been able to establish that screen time of any sort (regardless of the media) has any real benefit for very young children. This is why the American Academy of Pediatrics believes that infants younger than two years shouldn’t have any screen time. Media companies and advertisers of infant-oriented products may tell you otherwise, but their interests are probably not the same as yours when it comes to the best interests of your child.

Many of your child’s most basic preferences and habits are developing between the ages of 2 and 5. Simply put, the prevailing wisdom is that electronic babysitters offer no substitute for the physical activity and social interaction kids need at this age. In fact, to the extent that they encourage inactive, solitary play, they may actually pose real health risks on several fronts.  For instance, if your child is sedentary, he or she may have an increased risk of obesity, diabetes and heart disease later on, and may be slower to develop physical skills. If he or she doesn’t have regular social interaction with other adults and children, emotional problems and depression may be more likely.

By challenging your young children with a broad range of physical, intellectual and social activities, you offer them a developmental advantage. While media may have a place in the mix, experts agree that it should be a small one. Television specifically geared to preschoolers (think Sesame Street) can help expand your child’s awareness of learning concepts, but it shouldn’t be occupy more than an hour a day.

Between 5 and 8 years old, children can handle a little bit of screen time without it jeopardizing their development. Just be sure to set firm limits and encourage them to spend at least some of their screen time doing things that will enhance learning and hand-eye coordination.

As your children grow older, teaching them to live within certain sensible limits (in this case, by regulating screen time) and explaining why these limits exist can help them begin to look out for their own health and develop their own sense of self-discipline. Life lessons like these have value in and of themselves. So while your kids may not appreciate your efforts to restrict their use of electronic media, there can be very real longer-term benefits for your kids and for your family as a whole. It’s worth the effort!