Is your baby unsettled or having trouble sleeping because of gut pain?

The research tells us that green stools and mucous in the stool are normal for our babies, whether breastfed or formula fed. Sometimes there can be quite a lot of mucous. But green stools and mucous in the stool aren't signs of worrying inflammation, allergy, lactose overload, gut dysbiosis or gut problems, despite what you might hear. Frequency and consistency of baby stools often vary in the one baby, too, and this changeability is more pronounced with the introduction of solids. Please see your GP if you find blood in your baby's stool, or have concerns about your baby's health.

Gut pain very rarely causes baby sleep or crying problems

It's common for parents to say that when they put their baby down, the little one wakes or begins to cry. Have you found that every time you finish a feed and carefully place your baby down on his back, he starts to arch his back and cry? Is this caused by gut pain?

You might also find that you're lying awake a lot of the night listening to your baby groan and grunt. Parents describe how their little one arches her back or seems to writhe as if in pain, even with her eyes closed. Is this caused by the gut?

Next thing, she pukes, or burps, or breaks wind. Is air-swallowing or gas the cause of all this squirming? Or is it reflux pain in the oesophagus? Perhaps someone has suggested that this behaviour is caused by a lactose problem, or by gut dysbiosis.

Occasionally, in the first couple of months of life, a breastfed baby has a true lactose overload which really does cause gut pain and discomfort, and might disrupt night-time sleep. You can find out about lactose overload here. In this case, there is nothing wrong with either your milk or your baby's gut and enzymes, but your baby will settle down quickly once you experiment with some changes in the way you manage breastfeeds.

Otherwise, your baby usually isn't experiencing gut discomfort or pain when he back arches or groans and grunts or fusses a lot with being put down or feeds, despite everything you hear.

Babies most commonly dial up for long periods in the night because their sleep regulators aren't in sync with yours

Babies groan, grunt, writhe, and arch their backs because their sympathetic nervous system is dialling up, not because of pain. The gut is like a second brain, highly innervated including by the sympathetic nervous system. As the sympathetic nervous system dials up, your baby’s gut activates. This is why you might hear her swallowing back reflux, or burping, or passing flatulence or wind. Your baby's sympathetic nervous system dials up as she rouses from sleep, even though her eyes are still shut.

Your baby will have trouble settling into deep or quiet sleep when the sleep pressure is no longer very high. He may still slip in and out of light sleep, but there is not enough sleep pressure for him to go back into a block of deep sleep. Each time he surfaces into waking, he starts to dial up. And then his gut activates.

Experiment with this yourself and see what you think. Parents are usually relieved to flip the popular understanding, and realise that it's not gut pain which causes baby to dial up - but that it's the dialling up which activates the gut! It can be reassuring to know that your baby will be taking the amount of sleep that she needs overall anyway, because we can trust her sleep regulators to do their job over a 24-hour period. The problem right now is that her sleep pattern is fragmented and not aligned with your own sleep needs.

Our task is to work together on getting your baby's body clock and sleep pressure in sync with your own sleep regulators, just as quickly as possible.

Debunking the theory that gut dysbiosis causes pain, which then causes unsettled baby behaviour

Despite what you might have heard, you don't need to worry that

• Your unsettled baby has uncomfortable or painful gas in her intestines (other than in the case of lactose overload in breastfed babies, which is a breastfeeding management problem)

• Your baby's crying is caused by gut inflammation. It's true that excessive crying is a pro-inflammatory state in babies, which alters their gut microbiome, but this doesn't result in pain.

It's quite common for theories about baby behaviour to be taught as fact. This has happened, for example, with the hypothesis which proposed that gut dysbiosis causes wind pain, which causes babies to cry or causes their sleep to become disrupted.

Here's some information about your baby's gut microbiome, which is proven in the research.

• Your baby's gut is inhabited by highly diverse microorganisms, which make up the gut microbiome, and include populations of bacteria, fungi, viruses and protozoa

• Your baby's gut microbiome interacts with gut permeability, nutrient absorption, metabolism, the developing immune system, and protects against overgrowth of any one organism

• Your baby's gut microbiome populations are highly variable in the first 12 months of life, and will also be very different to another baby's gut microbiome, even when fed the same

• Breastfed babies have

  • Less diverse populations of bacteria compared with exclusively formula fed babies

  • More of the inflammatory factor calprotectin in the stool

• Babies who cry a lot don't have less diverse bacterial populations but have different colonisation patterns and increased variability in their gut microbiome compositions

• Babies who cry a lot have increased calprotectin in the stool

• Commonly used medications, including anti-secretory medications and antibiotics, make baby's gut microbiome less diverse.

The interactions between the gut microbiome and brain are complex, and the interactions between the gut microbiome and gut are also complex. It's much too simplistic (and also not corroborated by evidence) to say that an unsettled baby has a gut dysbiosis, which causes gut inflammation, which causes gas and pain, which causes disruption to sleep and crying.

It is possible to make sense of baby's behaviours in ways which don't blame your baby's gut (unless your little one has a true disease of the gut). The Possums Sleep Program offers a different way of making sense of your baby's behaviours, so that the days and nights with your baby become as relaxed and as enjoyable as possible, without using unnecessary diagnoses.

Selected references

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