Baby Month: Cows’ Milk Allergy
Tuesday, March 10, 2020

Cows’ milk allergy (CMA) is one of the most common childhood food allergies. It is estimated to affect between 2% and 7.5% of babies under one year old. Most children grow out of it by the age of 5, with the majority having grown out of it by age 3.

When does it develop?

CMA typically develops when cows’ milk is first introduced to a baby’s diet. This can be either in formula or when your baby starts eating solids.

More rarely, it can affect babies who are exclusively breastfed as cows’ milk from the mother’s diet can pass through to the baby this way.

Two main types:

  • Immediate CMA - symptoms typically start within minutes of ingesting cows’ milk
  • Delayed CMA - symptoms typically start to show several hours or even days after ingesting cows’ milk


      Allergy or intolerance?

      Babies can be either allergic or intolerant to milk. The symptoms can be similar, so it can be difficult to diagnose. A milk allergy involves an immune reaction to one or more of the proteins in milk. A milk intolerance does not involve the immune system and is caused by an inability to deal with certain substances in milk, such as lactose.

      Lactose intolerance is when some people don’t produce any or enough of the enzyme lactase which breaks down lactose. As a result, undigested lactose causes diarrhoea, bloating and wind.

      Recognising a milk allergy

      If a baby is allergic to milk, they will react to infant formula based on cows’ milk and sometimes (although rarely) to breast milk if the mother as recently consumed cows’ milk products.

      Symptoms include:

      • Stomach cramps
      • Vomiting
      • Diarrhoea
      • Rashes
      • Hives
      • Eczema
      • Difficulty breathing

      Individual symptoms could be related to a bug, however if the baby is affected in two separate areas like the stomach (vomiting) and the skin (hives), then you should ask your health visitor or doctor for advice.

      It is common for babies who are allergic to cows’ milk to be allergic to sheeps’ milk and goats’ milk as well, as they contain similar proteins.

      Diagnosing a milk allergy

      There is no single diagnostic test for cows’ milk allergy. A combination of tests and a series of elimination and reintroduction diets are often necessary.

      Giving your doctor as much information as possible about your baby’s symptoms can help speed up the diagnostic process. Keep a diary of their symptoms – when they occur, how long they last for – can help the doctor identify or rule out a cows’ milk allergy. Take photos of any skin reactions that might occur, such as a rash, and show these to your doctor too.

      Make sure to advise your doctor if there is a history of allergy in your family.

      Feeding & milk allergies

      Managing a cows’ milk allergy in your little one involves removing all cows’ milk from your baby’s diet, so it is essential to always read the ingredients on food labels. Common allergens, like milk, must be declared on pre-packaged goods.

      If a baby is being fed formula and has been diagnosed with cows’ milk allergy, your doctor may prescribe an extensively hydrolysed formula. The protein in this type of formula has been broken down into smaller pieces so the baby’s immune system does not recognise it as an allergen. This break down process does not affect the nutritional value of the formula.

      Soya formula is not recommended before 6 months of age as it contains phytoestrogens (plant-based compounds with oestrogen-like properties) and infants who react to cows’ milk-based formula often also react to soya-based formula.

      In rare cases, the baby may be reacting to the milk proteins passing from the mothers’ diet into breast milk. If a breastfeeding mothers’ baby is diagnosed with cows’ milk allergy, she may have to change her diet, however this would be quite rare.

      Identifying lactose intolerance

      A baby with lactose intolerance tends to experience less severe reactions than a baby with a milk allergy. As with a milk allergy, symptoms of lactose intolerance can include:

      • Diarrhoea
      • Vomiting
      • Stomach cramps

      Symptoms do not usually include hives or breathing difficulties, as with a milk allergy.

      Another difference is that lactose intolerance will not show up in a blood or skin-prick test. However, the baby’s reaction will be noticeable, despite not being as severe as that of a milk allergy.

      Two main types of lactose intolerance:

      Primary lactose intolerance

      Caused by a deficiency in the enzyme lactase. It normally affects Hispanic, Asian and American Indian populations, but is uncommon in Europeans. Primary lactose intolerance doesn’t mean that lactose must be removed from the diet entirely. Depending on the person, those with primary lactose intolerance can often tolerate a certain amount of lactose.

      Secondary lactose intolerance

      Usually caused by damage to the gut, after a severe stomach bug for example. However, this form of lactose intolerance is usually temporary, until the gut heals. In very severe cases, lactose may need to be removed from the diet for a few weeks.

       Pop in to your local CarePlus Pharmacy and speak to our designated Baby Advisers if you need any advice.