Cow’s Milk Protein Intolerance, Cow’s Milk Protein Allergy, Milk/Soy Protein Intolerance, milk allergy. These are the most common allergies in infants, affecting approximately 1 in 10 infants under the age of 1.

For my allergy baby, this was where our journey began. Weeks of vomiting, screaming, weeping rashes on her face, horrible nappies and sleeplessness led to the diagnosis of CMPI or cow’s milk protein intolerance. As I was breastfeeding at the time I removed all dairy from my diet to see if things improved. At the same time, I removed all soy also. 1 in every 2 babies intolerant to milk protein is also intolerant to soy protein. For us, this made a big difference in the baby. It was far from the whole story for us, that’s for sure, but it was a step in the right direction.


So let’s look at the facts.

  • 1 in 10 infants under 12 months are intolerant to milk protein
  • 1 in 2 of these group are also intolerant to soy
  • 90% of these infants outgrow their intolerance by the age of 2
  • Yes, the milk proteins can pass into the breastmilk in some women meaning a change in maternal diet or move to the dairy free formula is necessary
  • A very small percentage of these children will go on to be diagnosed with a milk allergy, with more severe and life-threatening symptoms possibly leading to anaphylaxis

Symptoms of cow’s milk protein intolerance or allergy in babies include the following

  • Vomiting
  • Diarrhoea
  • Constipation
  • Rashes
  • Irritability and sleeping issues
  • Slow weight gain
  • Stomach pain
  • Mucousy or bloody stools

There is also the possibility of a more severe allergic reaction or anaphylaxis characterised by the following

  • Difficulty breathing
  • Swelling of the face and airway
  • Collapse
  • Vomiting
  • Widespread rash
  • Feeling of impending doom




Probably the most difficult part of this allergy is avoiding the allergen. This is mainly due to the fact it is in freaking EVERYTHING!!!!!!!!! And it also has over a dozen different names it can go by. Below is a list. It is not all but most of the ways dairy can be hidden.

Milk- powdered, condensed, skim, full fat… anything milk! Butter, buttermilk, butterfat, ghee, yoghurt, cheese, cottage cheese, curds, custard, whey, casein, caseinates, kefir, lactose, sour cream etc etc etc etc… The list could honestly go on forever.

So could the list of things to be careful of. Basically, you need to read every packet and suspect every food. Especially takeaway and restaurants.


Before this post gets too long and boring with too many facts and confusing alternate names for dairy, it is super important to touch on the difference between cow’s milk protein intolerance or allergy and lactose intolerance.

CMPI/CMPA is a reaction of the body’s immune system to the proteins in milk. Lactose intolerance is an inability of the body to breakdown the sugar in milk known as lactose. This is due to an enzyme not being present. These two conditions are very different. one is protein, one is sugar. Lactose intolerance in babies is very rare. It is generally associated with adults whose bodies no longer produce enough lactase to breakdown lactose and they suffer from gut issues after having dairy such as bloating, flatulence, diarrhoea and stomach pain.

Simply avoiding lactose is not enough for babies with CMPI/CMPA. In fact breastmilk itself is high in lactose and babies’ guts are well equipped with lactase to break this down. To treat CMPI/CMPA the person must avoid all dairy, as listed above.


Diagnosing CMPI/CMPA/milk allergy can be complicated, as can be avoiding dairy. It is important to seek medical advice if you feel you are possibly caring for a baby with this medical problem. Paediatricians and immunologists are generally the best to diagnose. Have a chat with your GP, maternal health nurse or lactation consultant if you are concerned. You do not have to go it alone when it comes to cow’s milk protein intolerance or allergy. There is so much help out there!


For help with all the names of hidden dairy, grab our cheatsheet here! (Insert link


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