How Sleep Affects Brain and Physical Development for Babies

Baby Sleep

Sep 14

Did you know that most of your baby’s brain development happens while they’re sleeping? Not only that, but sleep also plays a vital role in your baby’s behavioral and physical health!

This may go without saying; but when your baby sleeps well, they are more likely to be in a better mood, socialize more, eat better, and process important information more efficiently.

Not to mention that when they are happier, we are happier!

How Sleep Affects Brain Development

Your little one needs a certain amount of sleep in a 24-hour period (dependent on their age) to function at their best and aid in brain development. Since this much-needed sleep can’t all happen during the night, napping during the day is so important and will ensure that these sleep needs are met and that your little one is feeling their best.

Studies have shown that since sleep plays a large role in memory, generalization, and word learning, children that aren’t getting enough sleep have poorer cognitive performance [1].

Your baby is constantly learning new things, both while awake AND asleep! This rapid brain development can be tiring for little ones and they can become easily overstimulated. This is another reason why naps are crucial. Naps allow your baby’s brain to process and store what they’ve been learning throughout the day and get some much-needed rest, physically. Then when they wake up they’ll be able to do it all over again!

If your little one is struggling with naps, check out my sleep courses by age!

How Sleep Affects Physical Health

Next to brain development, children’s physical health is also affected when they do not get enough sleep! Some health aspects that have proven why sleep is essential for babies are:

Growth: In the first few months of your little one’s life, sleep takes up nearly 50% of their time [2]! The growth hormone is primarily secreted during sleep, especially deep sleep. Making sure that your child is getting the correct amount of sleep as well as getting the best sleep possible can aid tremendously with growth.

Weight: Did you know that children who don’t get enough sleep are at a higher risk of obesity? [3] This is because when we are sleep-deprived, the hormone responsible for helping us to know when it’s time to stop eating can become unbalanced and not work as effectively [4]. Once infants reach 6 months of age, on average, night wakings are most likely not caused by hunger (of course, this is something that should always be determined by each baby’s pediatrician). When we use feedings as a way to help our children fall back to sleep, not because they are truly hungry, they become more at risk of obesity. Using other soothing techniques can not only help prevent this; but also, help ensure we are meeting our child’s actual needs and help them to become more independent sleepers.

Heart health: We already know that poor sleep quality and short sleep duration in children lead to issues with concentration, increased behavioral issues and impulse control, and learning; but recent studies also show that poor sleep is linked to disrupted autonomic nervous function, which predicts cardiovascular health. Continued unnecessary night wakings, sleep latency, and low sleep efficiency are related to unhealthier heart rate variability patterns, which shows the importance of a high quality of sleep for cardiovascular health in children. [5]⠀

Immunity: Think of the last time you were sick. Did you feel like you could go out and run a marathon? Probably not. Instead, your body most likely went into recovery mode and forced you to slow down and rest. Your little one is the same way! Waiting until they are under the weather to make sure they are getting enough sleep though won’t be enough. Your child produces infection-fighting proteins while they are sleeping, making sleep an immune booster!

Do Daytime Naps Affect Nighttime Sleep?

It may seem like holding out on daytime sleep would make your child sleep better at night, but quite counterintuitively, the opposite is true. Children are different from adults and their nighttime sleep is highly impacted by their daytime sleep [6]! When children do not get daytime sleep, they can become overly-tired and tend to take longer to fall asleep, have more night-wakings, and, in general, sleep less.

Your little one has a unique bi-phasic sleep pattern, which includes both napping and nighttime sleep [7]. You want to make sure though that your child’s sleep is sufficient throughout the day for their age. It is completely normal for babies to “cat nap” and only take 30-minute naps (or only one sleep cycle). Though it’s developmentally common for babies to begin to connect sleep cycles during the day closer to 5 months of age, there are absolutely ways to help lengthen naps! If your baby is taking short naps, here are some things to take into consideration for what could be causing this:

Short Nap Culprits

The room is not dark enough

It’s too early or too late in the day
You’re putting your baby down drowsy (instead of completely awake, allowing them to fall asleep on their own)
Your baby needs external help falling back to sleep (ex: feeding, rocking, shushing to sleep)
Your baby is not getting full enough feeds and could be hungry when going down for a nap

Tips to Lengthen Naps

Do your best to use sleep “props” to soothe your baby, not put them to sleep in the first instance (ex: feeding, rocking, patting, shushing, paci, on your body - TO sleep)

Create the ideal environment for sleep
Rush in to put your baby back to sleep however you can if they are still under 6 months (i.e. patting, shushing, contact napping, etc. to get baby to sleep another cycle)
Leave your baby in their sleep space for their full “nap time” (i.e. if your baby isn’t upset or crying, wait to see if they are able to fall back to sleep on their own)

Well-rested babies have been shown to sleep better during the night and as a result, take better naps during the day. It’s a continuous cycle that we can, as parents, keep an eye on to make necessary changes to as needed. A well-rested baby is a happier baby!

If you find yourself still struggling with your little one’s sleep, please know that you are not alone and that I am here to help. Check out my comprehensive sleep courses for babies and toddlers 0-3 years old.