Does it really matter what time your child goes to bed at night? Looking at the science, it does! It is important that kids have a bedtime that is both consistent and age-appropriate. Having a regular, age-appropriate bedtime allows children to get the sleep their brains and bodies need to grow and function at their best.
Bedtime Should Be Regular
What does it mean to have a regular bedtime? This simply means that bedtime is consistent from night to night for children who no longer nap. For children who do nap, it should be after a consistent number of hours awake (known as wake time) following their last nap.
Bedtime Should Be Age-Appropriate
What does it mean to have an age-appropriate bedtime? This means that the bedtime allows the hours of nighttime sleep needed based on the child’s age. For instance, most 1-year-olds need 12 hours of sleep at night. If they need to get up at 7:00 am, they should go to bed close to 7:00 pm so they are able to get the full 12 hours of sleep.
Our 21st century lifestyles don’t always make it easy to have children in bed at a consistent, age-appropriate time. Although there are certainly times for exceptions, your child’s bedtime is worth prioritizing as much as possible. A well-rested child will be your reward!
Why Does A Regular, Age-Appropriate Bedtime Matter?
Sleep needs per 24 hours decrease as children grow. However, even teenagers need 8-10 hours of sleep at night to function at their best. Sleep is necessary for growth and restoration of the brain and body. When children consistently get too little sleep, they accumulate a sleep debt. This means that the child is chronically overtired and thus not functioning at their best.
Overtired children often have multiple night wake-ups and/or rise for the day very early in the morning (before 6 am). They also tend to become very hyper and wound up or are very emotional, fussy, and tantrum prone; this is especially true in the latter part of the day.
Science Favors Regular, Age-Appropriate Bedtimes
There are studies that show detrimental effects when children have a bedtime that is either irregular or allows for too little sleep. Proven effects include difficulty regulating emotions, problems with attention, problems with memory, and problems with impulse control and judgement.
A study out of the UK published in the Journal of Epidemiology and Community Health looked at 11 thousand children. This interesting study showed that children who had a regular bedtime at age 3 but an irregular one at age 5 had worsening behavior over time. The good news is that this change in behavior was reversible when a regular bedtime was instituted.
Another study, published in the Journal of Pediatric Psychology, looked at 32 children between the ages of 8-12. It specifically evaluated their ability to regulate emotions, their math fluency, memory, and attention. These were measured both objectively and subjectively. The study lasted three weeks. All children had their baseline bedtime for the first week and were then tested to get baseline results. For the second week the children consistently went to bed either an hour earlier or an hour later; testing was repeated at the end of the week. The children then swapped to the opposite bedtime for the 3rd week and were tested a final time. Both objective and subjective test results showed impaired performance after the week of a later bedtime.
The Circadian Rhythm
We know that a child’s behavior is impacted by the consistency of their bedtime and the quantity of sleep, but why is this? The answer is the circadian rhythm. In its simplest terms, this internal clock is based on the naturally occurring cycle of light and dark. In addition to being the driving force behind night time sleep (naps are controlled by a different mechanism called sleep pressure), the circadian rhythm also controls a great many biological functions.
This internal clock sets itself based on exposure to light and dark (why a dark, sleep friendly bedroom is important!). It works best when this exposure is consistent from day to day. The circadian rhythm drives our bodies to produce sleep-friendly hormones in the evenings and alerting hormones around our usual morning wake time. When our morning wake times and evening bedtimes vary wildly, this internal clock becomes destabilized and does not support sleep to the best of its ability.
When a child has a regular, consistent bedtime, they are able to benefit from a daily dose of sleep-friendly hormones coming at the optimal time as their circadian rhythm will be “set” to this bedtime. With a varied bedtime, the child may miss this sleep-friendly window. This can be problematic as the brain, in an effort to stay awake, will produce alerting hormones thus creating a “second wind”. During this period of time, it will be very difficult for a child to settle to sleep.
When Should My Child Go To Bed?
There is no set time that is 100% the best bedtime for all children of a given age; some will need with an earlier bedtime while others may function just fine with a later one. The two important things are that the bedtime is consistent and allows for adequate hours of sleep. That said, many young children’s “second wave” will hit around 8:00 pm if they are not already asleep; leading the majority of young children to do best with a pre-8:00 pm bedtime.
You know your child’s bedtime is correct and age-appropriate when they wake happy most mornings, are able to sleep through the night without difficulty (aside from 1-2 quick feedings up to 9 months of age), are able to nap well if napping, and are able to maintain an overall pleasant demeanor in the late afternoon.
When children have sleep struggles, it is rare that there is a single causative factor. Usually it is a combination of schedule, sleep environment and sleep associations. If changing your child’s bedtime does not help and you would like assistance working out your child’s sleep struggle, please reach out for one-on-one support!