Is My Baby Allergic to Dairy?
Understanding Signs, Symptoms, and What to Do Next
Feeding your baby should be a peaceful experience — but for many parents, it’s quickly overshadowed by worries: Why is my baby so unsettled? Why the rashes, the reflux, the endless crying?
If you’ve started to wonder whether dairy might be the culprit, you’re not alone. Dairy allergies (and intolerances) are surprisingly common in infancy — and often missed in the early days.
At Neutral Nest, we believe in calm, informed parenting. So here’s what you need to know about dairy allergies in babies — explained gently, clearly, and without panic.
First Things First: What Does “Dairy Allergy” Actually Mean?
There are two main ways a baby can react to dairy:
1. Cows’ Milk Protein Allergy (CMPA)
This is an immune system response to the proteins found in cows’ milk — either through formula or breast milk (if the parent consumes dairy). It can be:
IgE-mediated (immediate allergy)
Non-IgE-mediated (delayed allergy)
2. Lactose Intolerance
This is very rare in young babies and involves trouble digesting lactose, the sugar in milk — not the protein. It’s more common in older children and adults.
For most babies, CMPA is the issue, not lactose intolerance.
Signs Your Baby May Be Allergic to Dairy
Not every baby will show all of these symptoms — and some may have only one or two.
Common symptoms of CMPA include:
Frequent vomiting or reflux
Blood or mucus in stool
Diarrhoea or constipation
Chronic wind or colic-like crying
Eczema or unexplained rashes
Persistent nasal congestion or wheezing
Feeding refusal or distress during feeds
Poor weight gain or growth issues
Excessive crying or general discomfort, especially after feeding
If these symptoms appear consistently — especially after milk feeds — it’s worth speaking to your GP or health visitor.
Breastfed Babies Can React Too
Even if your baby is exclusively breastfed, they can still react to the cows’ milk protein you consume in your own diet. While the amount passed through breast milk is small, for sensitive babies, it may be enough to cause symptoms.
Don’t feel guilty — you’re not doing anything wrong. If anything, your intuition for spotting a pattern is exactly right.
What to Do If You Suspect a Dairy Allergy
1. Track Symptoms
Start a food and symptom diary:
Note your baby’s feeds, your meals (if breastfeeding), and any symptoms
Look for consistent patterns (e.g. symptoms 2–3 hours after you eat dairy)
2. Speak to a Healthcare Professional
Contact your GP or health visitor. They may:
Recommend a trial dairy elimination from your diet (if breastfeeding)
Suggest switching to a hydrolysed or amino acid-based formula (if formula-fed)
Refer your baby to a paediatric dietitian or allergy specialist
Avoid switching formula or cutting out dairy on your own without support — especially if breastfeeding. Nutritional balance is still important for you, too.
How Long Does It Take to See Improvement?
If your baby has CMPA, symptoms often begin to improve within:
2–3 weeks of cutting out dairy
But full gut healing can take 4–6 weeks or more
This requires patience — but many parents report a dramatic difference in mood, sleep, digestion, and skin once dairy is removed.
What Happens Next?
Your GP may recommend keeping dairy out of your baby’s (and/or your) diet for several months
Around 6–12 months of age, they may guide you through a milk reintroduction ladder to see if your baby has outgrown the allergy
Many babies do outgrow CMPA by 18–36 months
In the meantime, there are excellent dairy-free alternatives — and you're not alone in navigating this path.
Final Thoughts
Wondering whether your baby is allergic to dairy can be overwhelming — especially when sleep is scarce and feeds are fraught. But trust your gut. You know your baby better than anyone else.
With the right guidance, the right support, and a little time, things can (and often do) get better.
At Neutral Nest, we’re here to help you move through these challenges gently — with calm advice, soft essentials for sensitive skin, and resources to support your journey, one feed at a time.