Is Food Allergy causing my baby's colic?
Is Your Baby Struggling with Colic?
As Paediatric Allergists, we often see families who are exhausted and emotional due to their infant’s colic. It is very distressing when your baby appears to be in continuous pain for no medical rhyme or reason. Colic can have a massive impact on the mental health of the entire household.
While "the three-hour rule" is used for a diagnosis of Colic (after the exclusion of all else), this remains a very long time to be comforting an inconsolable, screaming baby. Parents are understandably keen to know whether a food/food allergy is causing their infant obvious discomfort.
Please read on for an update re our understanding that colic is seldom due to food allergy and more often linked to an imbalance in a baby's developing gut bacteria (the microbiota).
What Is Colic?
As Paediatricians, we usually diagnose colic using what we call the "rule of threes." To officially tick the box for colic, an otherwise healthy and well-fed (and fed with good technique) baby, needs to be having bouts of inconsolable crying that last:
More than 3 hours a day...
More than 3 days a week...
For more than 3 weeks in a row.
How long will this last?
It’s an exhausting cycle for parents, but there is one major silver lining: it is "self-limiting."
Most babies start showing symptoms between 2 and 16 weeks of age, and in almost every case, the crying naturally tapers off by the three-to-four-month mark.
We also look for a typical diurnal pattern. Colic is rarely constant throughout the 24-hour cycle. The crying spells typically cluster in the late afternoon and evening.
If a baby is crying inconsolably for 24 hours straight without any settled periods, we would be much more concerned about a different diagnosis.
Diagnosis?
In Paediatric Allergy clinic, our first job isn't actually to "diagnose" colic—it's to rule out everything else.
Once we’ve completed a thorough physical exam and taken a detailed history to ensure they aren't ill or in pain for another cause, we can confidently label the symptoms as colic.
We will discuss the possible role of food allergies (in mom's diet if breastfeeding, or in formula options if formula-fed) and the use of probiotics.
Whilst allergies seldom play arole in this condition, it is a valid and obvious question for exhausted parents to ask, and there are a few other variables that can be put in place for babies at this age.
Infant and Maternal Diet and Colic:
Infant diet MAY be associated with colic through several proposed mechanisms, including: food hypersensitivity (especially cow's milk protein), gut microbiota composition, and gastrointestinal immaturity. The relationship is complex, multifactorial and not fully understood, but dietary interventions are commonly considered in clinical practice. Indeed, many of the infants who attend our clinic have already failed dietary intervention of some sort.
For breastfed infants, maternal elimination of cow's milk and other potential allergens may reduce colic symptoms, particularly when food allergy is suspected (eczema, hives, vomiting associated with high allergen intake in moms doet) or when standard management (correct feeding practices…) fails. It is important to note that the evidence for benefit is inconsistent and based on small, heterogeneous studies, so routine dietary restriction is not universally recommended by all Allergy and Paediatric Societies.
Nonetheless, some mothers report improvement with the elimination of specific foods, such as cruciferous vegetables (broccoli, cauliflower, kale, cabbage, bok choy, Brussels sprouts, and radishes), which offer vitamins, fibre, and sulforaphane/glucosinolates; however, these findings are not robust and may reflect individual variation.
In formula-fed infants, switching to a modified or non-mammalian milk formulae (e.g. extensively hydrolysed or amino acid-based formulas, modified rice formula, or infant soy-based formula) MAY improve colic symptoms, especially in infants with suspected cow's milk protein allergy. The use of Soy-based formula is no longer controversial, provided that soya allergy is excluded.
There is no substantial evidence supporting the use of fibre-supplemented or low-lactose formulas for colic.
Alterations in gut microbiota and markers of gut inflammation have been observed in some infants with colic, independent of feeding mode, suggesting that diet may influence colic via effects on the intestinal environment. However, the clinical significance of these findings remains unclear, and so we manage symptoms on a case-by-case basis.
Overall, while dietary modification may benefit select infants with colic, especially those with suspected cow's milk protein allergy or other food hypersensitivities, current evidence and ninternational guidl;ines do not support routine dietary changes for all infants with colic.
Management should be individualised, and parental reassurance remains a cornerstone of care.
And dont forget basics:
Holding the baby through the crying episode, gently rocking or even trying novel holding positions, but ensure safety from dropping - The "Colic Hold": Carrying the baby face-down across your forearm.
Reducing environmental stimuli.
Gentle motion (such as pushing the pram or rocking the crib).
'White noise'
Bathing the infant in a warm bath.
Ensuring an optimal winding technique is used during and after feeds.
Gentle abdominal light massage/tickling.
Avoid Simeticone (such as Infacol®) or lactase (such as Colief®) drops.
Avoid manipulative strategies such as spinal manipulation or cranial osteopathy (injuries have been reported).
Frequently Asked Questions
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Here are 10 common symptoms and signs of Colic:
Paroxysmal Crying: This is crying that starts and stops suddenly for no apparent reason. The baby might be perfectly happy one minute and in full-blown distress the next.
The "Inconsolable" Quality: Unlike hunger or a wet nappy, colicky crying doesn't usually stop when you feed, wind, or cuddle the baby. Movement in a pram or car is also often unsuccessful. It often feels like nothing you do makes a difference.
High-Pitched Screaming: The sound of the cry is often more urgent, piercing, or distressed than their usual "I’m tired or wet" whimper.
Flushed or Red Face: The intensity of the effort often causes the baby's face to become very red or even slightly dusky around the mouth during a peak episode.
Drawing Up the Legs: You will often see the baby pull their knees up toward their tummy as if they are experiencing abdominal cramping.
Clenched Fists: Physical signs of tension are common, particularly tightly balled-up fists and stiffened arms.
Arched Back: During a crying fit, the baby may stiffen their entire body and arch their back (this can sometimes overlap with reflux symptoms).
The "Witching Hour": While it can happen any time, symptoms classically peak in the late afternoon and evening (roughly between 4 pm and midnight) i.e. just when you want to relax!
Abdominal Distension (Bloating): The baby’s tummy may feel hard or look slightly "tight" and swollen during the episode, often due to swallowing air while crying.
Passing Gas or Drawing Up for a Bowel Movement: You might notice the baby seems to find temporary relief after passing wind or having a stool, though the crying often resumes shortly after.
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When we see a "colicky" baby in the clinic, our first job is to exclude other treatable causes. While we often categorise colic as a functional gut disorder, it’s rarely caused by just one thing. It’s usually a perfect storm of gastrointestinal immaturity, a shifting gut microbiome, and environmental factors.
However, as clinicians, we try our best to exclude alternate diagnoses:
Cow’s Milk Protein Allergy (CMPA): Both IgE and non-IgE mediated allergies can cause extreme distress. If a baby is formula-fed and inconsolable, or a breastfed baby is reacting to proteins in the mother’s diet, supervised dietary avoidance can be trialled. Non-IgE requires supervised elimination-reintroduction diet and IgE can be tested for with SPT and/or IgE.
Feeding Dynamics: It sounds simple, but aerophagia (air swallowing) from a poor latch or a fast-flow teat can cause significant abdominal discomfort. We also have to look for transient lactase imbalance following antibiotics or gastro-enteritis), which often presents with frothy, green stools and a very unsettled infant.
GORD: Standard reflux is common, but when it becomes Gastro-oesophageal Reflux Disease, the associated oesophagitis can mimic the paroxysmal painful crying of colic.
The "Must-Not-Miss" Red Flags
If a baby presents with excessive crying, we will need to exclude:
Intussusception
Malrotation with Volvulus
Non-Accidental Injuries
Infection
Systematic Clinical Workup
A standard "colic" consult should involve a deep dive into the following:
Detailed Feeding History: Method, volume, frequency, and maternal caffeine or spicy food intake.
Stool Patterns: Are they passing blood or mucus? (Points towards CMPA or infection).
Physical Exam: A head-to-toe check, including a look inside the nappy for strangulated hernias, and a palpation of the abdomen for masses or distension.
The Bottom Line:
By ruling out the red flags and considering dietary triggers like CMPA early on, we can provide much more targeted relief for both the infant and the exhausted parents.
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The Role of Breastfeeding
Breastfeeding remains the gold standard and should be encouraged and continued.
While maternal diet is often the first thing parents want to change, the evidence for routine dietary exclusion is weak.
We do not recommend blanket restrictions for all breastfeeding mothers.
However, if we have a high clinical suspicion of Cow’s Milk Protein Allergy (CMPA)—especially if the crying is paired with eczema, reflux, or stool changes—a maternal elimination diet (removing all dairy for 2–4 weeks) is a reasonable diagnostic step. If symptoms don't improve within that window, dairy should be reintroduced to avoid unnecessary nutritional restriction.
Formula-Fed Infants:
When we suspect a true sensitivity or CMPA, we select from:
Rice-based modified infant formula
Soy-based infant formula (if Soy allergy excluded)
Extensively modified Milk Formulae
Amino Acid Milk Formulae
What Doesn't Work?
It is equally important to counsel parents on what the evidence doesn't support. Currently, there is no robust clinical data to suggest that the following provide any significant reduction in crying time:
Fibre-supplemented formulas
Lactase-supplemented formulas (e.g., adding Colief drops routinely without evidence of lactose intolerance)
Alpha-lactalbumin enriched formulas
Clinical Summary
Dietary management of colic must be targeted rather than scattergun. We reserve specialised formulas or maternal restriction for cases where CMPA is a legitimate differential, characterized by:
Gastrointestinal distress (vomiting/diarrhoea)
Dermatological signs (atopic dermatitis/urticaria)
Failure to thrive or poor weight gain
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A Guide to Probiotics for UK Parents
Lactobacillus reuteri DSM 17938
If you’ve been searching for colic remedies, you’ve likely come across this specific strain. It is the most heavily researched probiotic for colic.
What the science says:
Reduced Crying: Studies show it can reduce daily crying time by 40 to 65 minutes.
The Breastfeeding Factor: The benefits are most pronounced in exclusively breastfed infants.
Efficiency: We have a "Number Needed to Treat" of 2–3. In medical terms, that is incredibly good—it means for every 2 or 3 babies given the probiotic, one will see a significant improvement.
Where to find it in the UK: The most common brand containing this specific strain is BioGaia Protectis (available as drops).
You might also find L.R. in infant formulas specifically marketed for "digestive comfort," though the evidence for formula-fed babies isn't quite as strong as it is for breastfed ones.
Bifidobacterium longum and Pediococcus pentosaceus (often shortened to BL+PP).
Where to find it in the UK: This combination is found in AB-Kolicare. It’s becoming more widely available in the UK and is a great option to discuss with your GP or health visitor.
Other Options: Bifidobacterium animalis lactis
Another strain often mentioned is B. lactis BB-12. In the UK: You’ll often find this strain in Optibac Baby Drops or Kendamil formulas. It is recommended by the European Society for Paediatric Gastroenterology (ESPGHAN) for breastfed babies.
Worried About Allergies? Let’s Help You Get Answers
If your child is showing signs of a food, pollen, or skin allergy, early diagnosis is key. At London Allergy Consultants, our expert team provides trusted, evidence-based care tailored to your child’s needs. From testing to treatment plans, we guide you every step of the way.
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London Allergy Consultants is a leading UK centre for diagnosing and treating food and airborne allergies in children and young people.
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