Will Starting Solids Help My Baby Sleep Longer?

Feeling exhausted and wished your baby slept longer? Hoping that starting solids might help? Sleep and nutrition experts weigh in on this hot topic.
tired mom in a yellow shirt holding a sleeping baby at a table

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This blog post is written in joint partnership with Jessica Painter, Certified Pediatric Sleep Consultant and owner of Sleepy Bunny Sleep Consulting and Jess and Nita, Registered Dietitians & co-owners of Happy Healthy Eaters

You’d be hard pressed to find a parent of a young baby who isn’t tired. All of those sleepless nights can leave parents feeling desperate for anything to help their baby sleep better. One of the most common pieces of advice is to start giving baby solids to help them sleep better, but is this even true? And if it is true, is it always the best thing to do? Is it without risk? Let’s learn.

Does starting solids earlier increase sleep duration?

When babies first start eating solids there may be some changes in gassiness and bowel movements (poops) which can cause discomfort, sometimes affecting their ability to sleep well. These temporary changes are due to their immature gut being put to work digesting foods that they’ve never experienced before, and as they grow and their gut matures, this discomfort should ease. But, is it still worth it to offer your baby solids early in order to help them sleep?

The answer is not as simple as it seems; we need more research!

While the World Health Organization, American Academy of Pediatrics and Health Canada all recommend starting solids at 6 months for the average baby, many families choose to start solids earlier with the goal of getting more sleep. A 2018 study published in JAMA pediatrics found that babies who were introduced to solids earlier (3 months vs the recommended 6 months of age) slept 7.3 more minutes each night overall, with the greatest difference at 6 months of age when it peaked at 16.6 more minutes per night (btw at Happy Healthy Eaters we strongly discourage starting solids earlier than 4 months).

Although this can sound promising, the study doesn’t come without limitations. Firstly, the study used parent recall to report on their child’s sleep which we all know can be difficult to remember, let alone down to the minute, especially when you’re tired and taking care of a tiny human!! More importantly, this study was actually looking at food allergies, so the main focus wasn’t even on infant sleep, potentially hindering the accurate reporting of sleep times.

Other research shows that babies who were introduced to solids early had NO LESS night wakings than those that waited to introduce solids until 6 months. This 2015 study concluded that although infants (4 months +) who were fed more during the daytime (milk and solids) had less night feeds, they still had the same amount of night wakings! As well, this systematic review of 4 studies (also using sleep recall) showed no differences in how long babies slept based off of when they were introduced to solids.

It’s also important to note that babies who start solids earlier than 4 months have been shown to sleep even less than other babies! This 2010 study showed a difference of almost 40 minutes less sleep per day (0.39hrs) than those that were not given solids. When it comes to sleep and those newborn stages, 40 minutes of extra sleep sounds like something most parents would definitely be into!

What we can gather from these results is that more research needs to be done to solidify our understanding of when to introduce solid foods to babies and the implications of beginning solids at different ages.

birds eye view of a blond baby in a high chair reaching for small pieces of steamed broccoli

What is the priority food for a baby? Breastmilk or formula.

Breastmilk and formula, which aims to mimic human milk’s nutritional composition as closely as possible, contain nearly 100% of what a baby needs to grow and develop healthily. From 0-6 months, the only extra thing most babies need is a daily Vitamin D supplement. 

Once they turn 6 months old, things change! The iron stores that the baby was born with start to deplete. At this point, high iron foods become an important addition to your baby’s diet. But breastmilk and formula still remain an important “catch all” for most other nutrients. 

“But my baby seems to be extra hungry all of a sudden. Doesn’t that mean she’s ready for solids?”

When a baby goes through a growth spurt, which often happens at 3 months and 4 months, your baby will certainly be showing more frequent signs of hunger or not being satisfied at the end of a feed. 

So yes, your baby does need more food!

But she doesn’t need a different kind of food, just more of what she’s already eating: human milk or formula!

At this age, your baby is likely not developmentally ready to start solids. It’s important for a baby to have the proper core strength and mouth mechanics (among other things), before introducing solids. 

Starting solids too soon can increase the risk of choking or that your baby will develop an aversion to solids.

Suggested readings: 

Why I Waited Until 6 Months to Start My Baby on Solids

How to Help Babies Gain Weight


“So how do I know when my baby IS ready for solid foods?”

While chronological age is an important factor, it’s not the only thing to consider when starting your baby on solids. You also want your baby to meet certain developmental milestones in order for the transition to be a safe and successful venture.  Your baby should be able to sit up mostly unaided, have good head and neck control, be able to bring objects to his mouth, and the extrusion reflex should be mostly diminished. These are all also gentle reminders to not compare your baby to others. Zero in on your baby’s developmental signs of readiness!

How can I tell the difference between if my baby is hungry or tired?

Past the newborn stage, a baby’s cues can be so hard to read, especially once they start to stay awake a bit longer. When your babe starts to fuss it can get a bit hazy trying to figure out what they actually want. Are they hungry? Tired? Bored? Sometimes we just don’t know!

It can help to understand that for both hunger and sleep cues, babies generally start off with more subtle cues, and if their needs aren’t met, they increase the intensity of those cues. Learning the differences between each type of cue and where it lands on the intensity scale while using their wake windows or time of day and your baby’s individual patterns, can help you decipher what your baby is trying to tell you about their needs.

Hunger CuesSleepy Cues
Early CuesMouth open
Smacking lips
Turning head
Red-ish eyebrows
Staring ahead
Looks away
Red eyes
Mild CuesHead bobbing
Hand to mouth
Rubs eyes
Intense CuesCrying
Turning red from crying
Agitated body movements
Frantic movements
Arching back
Pushes away
Rigid body

What do we know about iron and sleep?

We know quite a bit about how iron deficiency results in sleep disturbances…. in adults and children. Unfortunately, we don’t have a lot of research on babies. 

This one study showed that infants with iron deficiency anemia (a late stage of iron deficiency), resulted in sleep alterations that persisted even after the anemia was corrected. 

We try our best not to be fear-mongers here at Happy Healthy Eaters, but the truth is that the ill effects of low iron sometimes have lasting, irreversible consequences. Which is why “prevention is the best medicine” and it’s the reason we talk so much about the importance of high iron foods when starting solids!  

Anyway… rant over. Let’s get back to iron and sleep.

When the body is low on iron, there are a few ways this can impact sleep:

  • Restless legs syndrome
  • Periodic limb movements
  • Sleep disordered breathing
  • Attention-deficit hyperactivity disorder related sleep disorders
  • General sleep disturbances

Since we don’t have a lot of research directly on infants, iron status, and sleep, the best we can do is extrapolate from the older aged study groups and guess that babies’ sleep would be affected in a similar way. 

Is there another way that I can help my baby sleep better besides introducing solids early?

When looking at our children’s sleep, it’s important to remember that hunger isn’t the only reason our children wake. Knowing that, there are a lot of things that parents can do to support sleep for their baby that don’t include feeding (when they aren’t yet ready for solids). 

1. Set realistic expectations. It’s important to keep in perspective that everyone wakes in the night, even if they don’t remember it. In between sleep cycles, we briefly wake, but most often, we’re able to put ourselves back to sleep before even realizing that we’ve woken. This promotes the idea that sleeping “through the night” means absolutely no waking when in reality it’s a completely normal and a necessary biological function. It’s especially normal for younger babies to wake fully between every sleep cycle and is suspected to be a protection mechanism against SIDS (sudden infant death syndrome). But don’t worry, it’s also natural that they’ll get increasingly better at putting themselves back to sleep as they age!

2.Ensure that you’re following the fundamentals of sleep. There are three pillars to solid sleep hygiene for everyone, regardless of their age or parenting beliefs. Ensuring that your child’s environment, timing, and routine all promote sleep can create a space where your child’s body is working with you to sleep, not fighting against sleep. 

3.Remove any barriers to sleep. Ensure that there is nothing preventing your child from sleeping as peacefully as they can. Once the fundamentals are checked off, ensuring that there are no medical reasons that sleep is proving to be difficult can help put your mind at ease. Some conditions that can affect sleep include eczema, tethered oral ties (i.e. tongue tie, lip tie etc.), deficiencies (i.e. iron), etc. Addressing these first will help ensure your efforts for a peaceful sleep aren’t in vain.  

4.Seek out professional support. If your child’s sleep just feels overwhelming and is affecting other areas of life, it may be time to seek out a professional to help you get a clear vision of what’s affecting your child’s sleep and support you. It’s also important to find someone that respects your parenting philosophy!

frustrated parents looking at their crying baby lying on a couch

Sleep is complex!

There are so many changes that a 4–6-month-old baby is going through: the way in which they sleep is biologically different to when they were newborns, they start to become increasingly aware-of and participate in their environment, they’re getting better at holding their head up and starting to roll and grab things… etc. all of which can cause disruptions in sleep. It’s important to keep in perspective and remember that this is simply a phase, not forever!

It is also important to remember that sleep is complex and multifactorial, and hunger isn’t the only cause for disruptions. If you feel like you’re in the thick of it and don’t know what to do when it comes to your child’s feeding and sleep, it might be good to review expectations and ensure they are realistic for your little one, then explore ways to improve your situation that include holding off on solids until your child is developmentally ready.

For further support with your infant’s sleep, connect with Sleepy Bunny Sleep.

For further support in starting solids, take Happy Healthy Eater’s Start Solids Confidently course.

jess and nita, registered dietitians
Meet Jess and Nita

Hi! We’re both Dietitians & boy mamas! We’re here to help you confidently raise kids who will grow up to be lifelong Happy Healthy Eaters. Dig into our site for kid-tested recipes & feeding tips. 

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