Why Infant Sleep is Important

twins cuddled in sleep on fluffy pillowWe’re taught from an early age that sleep is important. Our parents and teachers try to tell us when we’re young. Yet, we rarely listen – because who’s got time for 8 hours of sleep every night, right?

Sleep is an essential building block for your child’s mental and physical health. But if you’re finding it impossible to help your toddler sleep, you’re not alone. The American Academy of Pediatrics estimates that sleep problems affect 25 to 50 percent of children and 40 percent of adolescents.

Understanding their sleep needs is the first step towards providing better sleep for your children. Through a combination of sleep hygiene, age-appropriate routines, and close attention to any sleep disorders, you can help your child get the rest they need to grow up strong and healthy.

Getting enough sleep is essential – and enough means more than the 8 hours you should be getting every day. Babies need more like 14 to 18 hours, depending on their age.


Most of baby’s brain development happens during sleep: literally. This is when the connections between the left and right hemispheres of their brains are being formed.

Brain synapses are formed during sleep: more than 1,000,000 million neural connections are formed per second during their first 3 years.

Memories are formed and stored: your baby’s brain stores what they’ve learned that day during sleep

Lack of sleep can cause bigger problems down the road: cognitive issues, developmental delays, etc. can sometimes be linked to not getting enough sleep

Research shows that sleep impacts many other areas of a child’s life, including:

  • Alertness and attention
  • Memory
  • Cognitive performance
  • Learning and vocabulary acquisition

Mood and resiliency

Sleep also has important effects on growth, especially in early infancy. In toddlers, napping appears to be necessary for memory consolidation, attention span, and motor skill development.

Sleep & the Infant Body: Under Construction

A newborn isn’t quite the finished article – the brain is not only learning and growing, the body is under construction as well during sleep. Some of the physical processes occurring during sleep include:


Parents laying on bed with sleeping baby in between themBabies double their birth weight by around 5 months and triple it by around 12 months. This is a lot of growth in such a short space of time, and good sleep plays an important role in this.

Somatotropin is a growth hormone which is released throughout the day, but “approximately 80% of it is released soon after a child or adolescent is in the Non-REM stage of sleep.” So not getting enough sleep can stunt their physical development.  One study conducted showed a link between increased bursts of sleep and growth spurts in body length, which showed that growth spurts both occur during sleep and are influenced by it – it is thought that this may be because of the release of somatotropin during sleep.

Weight gain

It has also been found that short sleep duration can lead to childhood obesity. Research found significant correlations between sleep and growth in babies’ first six months, and in another study which looked at 915 children found that daily sleep duration of less than 12 hours during infancy appears to be a risk factor for overweight and adiposity in preschool-aged children. (my emphasis)

So while good sleep helps them grow, less sleep can affect their weight in a negative way.

Mental development & learning

Your baby’s brain roughly doubles in size in their first year. They develop rapidly, and a lot of their learning is done while they sleep. Research reviewers looked at a number of studies focused around sleep and mental development in infants and found correlations between normal sleep development and higher developmental scores, and “higher motor activity and night waking negatively correlated with mental scores.” They also looked at studies that showed that children with ‘difficult’ temperaments slept less, and that increased sleep correlated with ‘easy’ temperaments, although this is difficult to measure.

Just like older children and adults, sleep is critical when it comes to memory consolidation. According to one research team, sleep allows infants to strengthen their memories and things they’ve learned while awake, prepares them for the processing and exploration of their environment and allows them to “process sensory stimuli and learn about contingencies in their environment.” This processing of information that happens during sleep is important, especially in the first year, as this is when a child is completely new to the world and is learning all about their bodies and their environment.

Immune system

Yawning baby

Sleep is important for our immune system at any age, but it is especially important for babies, as their immune systems are still immature and not as strong as adults. It takes time for immunity to develop, and sleep plays a role in this. If a baby is sleep deprived, they are more prone to disease and infection, and it can affect their recovery time. Being ill can also negatively impact their sleep, disrupting their sleep cycle and giving them less quality sleep overall.

Sleep & brain development: an important connection

In the womb, babies spend about 95% of their time asleep. And as soon as they make their entrance into the world, they’ll still spend the majority of their time sleeping—the transition from the womb to the real world is overwhelming and exhausting for a baby.

Not to mention, their bodies are in a state of rapid development—especially their brains. While they’re snoozing, memories are being stored, synapses are forming, brain tissue is developing, connections are established, energy is replenished…and a whole lot more.

Your Baby’s Brain and Sleep

In fact, your baby’s brain will double in size in their first year, and most of that growth will happen while they’re asleep.

However, your baby’s brain actually started developing while they were about the size of a small seed in the womb – possibly before a woman even realises she’s pregnant.

Dad holding babyYou know how people often repeat the words that a baby or child is “like a sponge?” It’s really true! By the time your baby is born have all the brain cells they will need for the for the rest of their life, and those brain cells are ready and eager to learn.

As your baby has new experiences, synapses and connections are formed, which means your baby is constantly learning. Their brain is storing these new learnings to be used for the rest of their life. This is how your baby will learn her name, what things are, who you are, etc. By 3 years old, your baby will have formed over twice as many synapses as the average adult.

This early brain development is essentially the building blocks for your baby’s future learning, health, and behaviour. The connections formed as an infant serve as an infrastructure for forming more complex connections when they’re older.

Your baby’s brain also has the incredible ability to change and grow – literally. In their first three years, your baby’s brain can actually create more grey matter by altering synapses. Babies and small children who suffer from brain injuries can recover much more completely than an adult who has the same injury.

Recharging the Brain’s “Batteries”

After a long day of learning, it’s time to recharge and store experiences in the brain. It’s like that for your baby too – but they need to re-charge more frequently than adults.  The sleep-eat cycle that most newborns quickly fall into is really more like a recharge-refuel cycle for their growing bodies and brains. Sleep allows your baby’s brain to absorb what it’s learned throughout the day and store it properly.

How Much Sleep is Normal in a Baby’s First Year?

The number one question parents ask is: “How much should my baby sleep?”

Answer:  There IS no definitive answer!

Newborns spend around 70% of their time asleep, sleeping often, but in short periods. When they’re awake, they need feeding, changing and lots of TLC, which leaves parents exhausted. As this sleep routine is very different to parents’ sleep, many worry over whether their baby is sleeping well. There are then extra concerns when the baby goes through phases of change in their sleep pattern.

So, it’s understandable that your child’s sleep can add to your worries, but it’s also important that you’re getting enough sleep yourself. Our previous post in this series looks at the importance of sleep for parents and the first post looks at the importance of sleep during pregnancy. In this post we’ll be focusing on where it all starts: the first year of your baby’s life.

The sleep pattern of an infant (or anyone for that matter) is dependent on a number of factors, the primary factor being the individual’s needs; therefore, what worked for one child in a family with regard to sleep may or may not be effective in their younger siblings.

There are guidelines, of course – but in the end, it’s regular observation of your baby and his/her habits that will unlock the key to their sleep pattern, once they actually establish one!

The chart below shows how much, on average, babies sleep during a 24-hour period. Of course, every baby is different and each baby’s individual pattern will change and evolve. Some babies can get by on less, and some may need more, so don’t worry if they aren’t sleeping for the average amount of time, or if their daytime and night time sleep patterns aren’t balanced in this way – they will gradually get into a rhythm as they grow. It is advised that at 0-3 months, they should sleep for more than 11 hours but less than 19, and at 4-11 months they should sleep for more than 10 hours but less than 18.

Graph of average hours slept by infants 0-12 months

However, if you think that your baby is sleeping too much or not enough, you should contact your healthcare professional.

In part 2 of the Babies and Sleep Series, we’ll look at some of the sleep problems that occur in children, as well as some solutions.

For additional tips on holistic and natural ways to get your baby sleeping peacefully, book a free Slip into Sleep session at https://meetingwithsheila.com


Sources: Bluebell, Sleep Foundation, Nested Bean