Knit Blog

It’s been a long day, and you’re exhausted. You’ve been running nonstop since 6 am. And as dinner is winding down, your son starts begging for twenty minutes of screentime. You know that a few minutes of Minecraft would finally get him out of your hair for a few so you can wash the dishes -- or better yet, sit down for the first time today.

You’ve heard that screentime close to bedtime is bad for sleep, but is twenty minutes of an online game really that bad? It can be hard to believe it enough to enforce it -- especially when you know you’ll be turning on the TV to veg out for an hour the minute your kids are finally down. If it’s okay for you, why is it so bad for your kids? Is the anti-screentime fuss really worth the battle?

If your child is sleeping well, you might feel like it’s fine to let him have those few minutes of Minecraft. But it’s possible that saying “no” to those twenty minutes now could cut back on an hour of repeatedly sending him back to his room once bedtime rolls around. Here’s why the screen might not be worth it (and why you should consider cutting out your own evening TV time, too).

What makes you sleepy?

The secret to the danger of screens lies in melatonin. This all-important hormone is the key message that signals your brain it’s time to feel sleepy. That means, for your child, melatonin is the biggest factor in whether bedtime will be an easy, relaxing time or an all-out struggle. When your child feels sleepy, he has no problem lying down and settling for sleep. When he’s feeling energized and hyper, bedtime becomes a battle.

Melatonin is produced by the pineal gland, and it gets “turned on” when lights get turned off. When the lights get dimmer, that signals the brain to start producing melatonin. In nature, of course, that gradual darkness comes every evening as the sun sets. In the modern world, though, there are a lot of artificial lights that interrupt that natural cycle -- and the truth is that any artificial light will reduce the body’s production of melatonin and negatively affect sleep.

However, the light from screens is even worse than regular light. The reason is the type of light emitted by your child’s favorite devices. Most screens give off a blue light, which has a wavelength on the shorter end of the spectrum. Sunlight has a longer wavelength, and the photoreceptors in your eyes are more sensitive to shorter wavelengths -- meaning that blue light looks brighter. So it’s no accident that blue light is the wavelength of choice for screens: the brighter light makes screens (especially small ones) easier to read. However, the brighter, hotter light of the shorter wavelength also suppresses the body’s production of melatonin even more than sunlight would. Looking at a screen at night is kind of like standing outside on a bright, sunny day. It’s telling your body it’s time to wake up -- not to slow down.

And when your child’s body doesn’t produce melatonin, he won’t feel sleepy. What’s worse, the feeling of sleepiness is actually delayed by around an hour after melatonin production begins. In other words, your child won’t feel sleepy until an hour or more after you cut off the screens. And he’ll need another thirty minutes to an hour after melatonin production begins before he will actually conk out. In other words, if you want him to fall asleep by 8, you should cut off screentime by 6 -- the same time that the sun is going down. And if you don’t, screentime in the evening could delay his bedtime by an hour or even two.

What can you do to cut back on the screens?

The best solution for evening screentime? Just say no. Don’t let your child play on the screen in the evening. But if it’s hard to go cold turkey, here are a few different techniques for reducing the light he’s exposed to at bedtime.

First, turn off all the lights in the house. Even if you do allow a little bit of screentime, remember that any type of light will suppress melatonin. So if you’re eating a peaceful dinner by candlelight, your child’s body will start to produce melatonin. Even if you allow him a few minutes of screentime after dinner, the impact may not be as bad, since he’s been sitting in the dark.  

Second, try adding filters to the lights that screen out the blue wavelength, making the light warmer and less bright. You can add these to regular bulbs (start with the ones in your child’s room) as well as to screens, to make the wavelengths he’s being exposed to longer and dimmer. However, again -- remember that the problem isn’t really blue light; it’s any light. So filters won’t solve the problem entirely. Your goal should be to cut out evening screentime entirely.

When you’re ready to make the transition to a screen-free evening, plan to cut off screentime two hours before bedtime. Keep in mind that bedtime doesn’t mean the time when you want your child to fall asleep; it’s the time when you start your bedtime routine. To calculate what time you should stop the screens, start with what time your child needs to wake up in the morning. Then subtract the ideal number of hours he should sleep. That gives you the time you want him to fall asleep. From that time, subtract the length of your bedtime routine, and then subtract two hours. That’s the latest hour when your child should be looking at a screen.

To make the cut off easier, try creating a ritual of putting the screens to bed. Enlist your child’s help in understanding why it’s better for his body to get better sleep, and talk with him about what would make it easier for him to give up screens at night. (For example, it might help to schedule a longer screentime session earlier in the day as he’s getting used to the new schedule.) Set a timer for “screen bedtime,” and when the timer goes off, say goodnight to the games and put them away until morning.

If your child is used to relaxing with his device before bed, the transition will be hard at first. But it can have a lot of benefits: in addition to better sleep, you’ll have more interactive family time in the evenings, and new traditions to enjoy together. Even better, you’ll soon find that as your child adjusts to the new routine, he’ll fall asleep faster and easier -- leading to more sleep overall, and better behavior the next day. After a few weeks of adjustment, you might discover that no one in your family misses those twenty minutes of Minecraft -- not even you.