Could your breastmilk be what's stopping your baby from sleeping? An expert answers.

Sarah and Tim called me desperately. They were exhausted and it seemed that no matter what they did, they couldn’t settle George, their four-week-old baby. George was squirmy and crying with tummy pains. He would only sleep for very short spells if he was held and rocked constantly.

I checked baby George’s feeding and attachment at the breast, took a history, including what kind of birth he had experienced and observed how Sarah and Tim were handling him. They were attuned parents resting at home. George hadn’t been bustled about by visitors or outings that may have overstimulated his immature nervous system. George had no issues such as a tongue or lip tie that could have contributed to his restlessness while feeding and no obvious preferred side.

His attachment was good and he was transferring milk well. Sarah’s diet was healthy and natural. So I asked if there were any foods she had craved or binged on during pregnancy. While there is a paucity of evidence and differing opinions about whether babies can be sensitised to foods in utero, it can often give a clue to what the mother may be binging on. Tired mums on automatic pilot often can’t really think straight.

“Yes, citrus –I couldn't get enough – oranges, mandarins,” said Sarah. I asked, “are you eating oranges now or drinking orange juice?” I am always specific because in a new mother mindset it’s easy to be a bit foggy. For instance, I have asked, are you eating dairy or chocolate? Mum will say “no” and Dad will ask, would you like a drink of Milo? This, of course, is milk and chocolate, both of which are common allergens?

Tim went to the fridge and brought out a two litre bottle of orange juice that was almost empty. He asked Sarah, “when did you buy this? I haven’t drunk any of it.” It turned out Sarah had bought the juice just the day before and had drunk almost an entire bottle all by herself. The good news is that when Sarah eliminated the citrus from her diet, little George became a calm settled baby – and it only took around 48 hours to make the difference.

If you or your partner suffer from allergies such as eczema, asthma or hay fever, or if there is a family history of allergies, there is a stronger possibility that your baby’s restlessness and poor sleep could be due to food sensitivity or allergies – and they could be reacting to foods passing through your breast milk (your baby is never allergic to your milk).

Food allergies in exclusively breastfed babies are caused by foods that pass into your breast milk, not to your breast-milk itself. Allergies in infants may cause symptoms including: colic, nausea, vomiting and reflux, wheezing and respiratory congestion, dermatitis, eczema, and various rashes (although other medical causes should be ruled out for these symptoms).

The most common culprit is cow’s milk protein (found in milk, cheese, yoghurt – butter is fat, not protein, so you may still be able to eat butter). In one study at a UK sleep clinic, 12 per cent of thirteen-month-old infants who presented with persistent night-waking for which no other causes were found, were taken off all milk products when cow’s milk intolerance was suspected.

In most of these children, sleep normalised within five weeks, with night-time awakenings falling to nil or once per night. A subsequent milk challenge (double blind) induced the reappearance of insomnia and, after a year, when the challenge was repeated, all but one child reacted as before.

Other foods that may cause allergies are peanuts, eggs, soya products, fish, wheat, citrus and chocolate. However, reactions to foods seem to vary widely among individuals. Some sensitive babies react even to small amounts of certain foods in their mothers’ diets, so allergy symptoms (including frequent night waking), can be alleviated by the elimination of offending foods from the mother’s diet.

The best way to protect your baby from allergies is to breastfeed exclusively for the first six months. If you are bottle-feeding and suspect allergies to cow’s milk, consult your doctor about trying a hypoallergenic formula (these are available on prescription but are very expensive otherwise).

Food additives are present in ever-increasing numbers in almost all processed foods and these can dramatically affect sleep patterns and behaviour. Some babies and children can also become restless after eating foods containing salicylates. These are naturally occurring chemicals which are found in otherwise healthy foods such as broccoli, grapes, apples, citrus and tomatoes as well as in some processed foods.

Like Baby George, who was sensitive to the orange juice his mother was binging on, I have seen remarkable changes in babies’ sleep patterns with simple tweaks to either mum or baby’s diets. An eight month old who loved broccoli (which is high in salicylates) but was waking up to ten times a night settled and woke at around 10 pm and at 5 am (but resettled after a breastfeed), when broccoli was eliminated. Other babies have slept well after the elimination of grapes and berries (also high salicylate foods) from their own and mum’s diets.

Tracking down offending foods in your child’s or your own diet may take some effort, especially for already exhausted parents, but in the long run it could gain you more sleep. If you think that sleeplessness may be related to foods in your diet passing through your breast-milk, keep a notepad handy and jot down your baby’s crying times and what you eat to see if they are linked.

If there appears to be a ‘cause and effect’ between foods in your diet and your baby’s crying, an inexpensive and simple solution is to eliminate the suspect food for at least a week, preferably two weeks. If your baby’s sleep patterns improve, you can either be thankful and avoid the suspect food, or you can reintroduce a small amount of the food into your diet – if the night-waking or allergy symptoms re-occur, you can be pretty certain you have ‘nailed’ the culprit.

Elimination of foods may take anywhere from a few days to several weeks to make a difference to your baby’s behaviour so allergies are difficult to prove or disprove, but if it calms your baby (and you), modifying your diet is a small sacrifice. Sometimes, sleep will be elusive without major dietary changes but in other cases it will just be a matter of balance, perhaps taking care not to overload on certain foods that seem to affect your baby.

A good guide to sensible eating is to include a wide variety of foods in as close to their natural state as possible. If you find the thought of changing your diet overwhelming, seek help from an appropriate professional such as a dietician.

Pinky McKay is Australia's most recognised breastfeeding expert. She's an Internationally Certified Lactation Consultant (IBCLC) and best-selling baby-care author and creator of Boobie Bikkies, all natural and organic cookies for breastfeeding mothers. For Pinky's tips to boost your milk supply naturally, download your FREE ebook "Making More Mummy Milk,Naturally"  HERE