Lactose Intolerance and Cow’s Milk Allergy are often confused, however they are very separate illnesses.
Lactose intolerance
This is when your baby has difficulty digesting lactose, the natural sugar found in cow’s milk. It is caused by low levels (or complete lack) of the enzyme lactase, which is needed to break down and digest lactose. Intolerance reactions do not involve the immune system.
Symptoms of lactose intolerance only involve the bowels and back passage. These include excessive wind, explosive diarrhoea, itchy bottom, tummy swelling and tummy ache.
It is exceptionally rare for babies in the UK to be born with lactose intolerance. It can however occur after a tummy bug where the infection has damaged the cells that produce lactose in the upper gut. Symptoms can last for about four weeks until the gut recovers and can start to break down lactose again. If your baby has a tummy bug and is formula-fed, your doctor may advise you to try lactose-free formula milk for a short time until they get better, at which stage their normal formula can be reintroduced.
Cows Milk Allergy (CMA)
The clue is in the name! This is an allergic reaction from your baby’s immune system to the casein and whey proteins in cows milk. It is the most common childhood allergy, affecting between 2-7% of children under 1 year of age. Having a family member with eczema or asthma is a risk factor. It is also seen in fully breastfed infants who react to cows milk proteins that are passed into the breast milk from the mother’s diet.
- Your baby could have an immediate reaction (usually within 20 minutes) after drinking or eating something with a dairy ingredient. Symptoms include facial flushing, a red itchy rash, watering eyes and a stuffy nose. It’s also possible they will feel sick or have diarrhoea, and rarely, a more serious reaction called anaphylaxis.
- Delayed allergic reactions are common too. For example, your baby could have eczema, acid reflux, colic, diarrhoea or constipation; and cows milk allergy could be one possible explanation.
The good news is that your baby is likely to grow out of their milk allergy. If your baby has delayed allergic reactions to milk, they will probably outgrow it by the time they are 3 years old. If they have an immediate allergic reaction, the allergy may last into their teenage years. But by the time they are grown-up, it is unlikely they will be allergic to milk at all, as it is uncommon in adults.
If the baby is formula fed, the first-line formula choice in suspected mild – moderate cows milk allergy is an extensively hydrolysed formula (eHF). Here the milk proteins are broken down into small fragments that are not so readily recognised by your baby’s immune system and therefore are not so likely to trigger an immune response. Examples of eHF’s are Nutramigen Lipil, Pregestimil Lipil and Aptamil Pepti. Some babies can still react to the remaining protein in eHF’s and require an amino acid formula (AAF). Amino acids are the tiny building blocks of a protein and are too small to be recognised by the immune system. Examples of AAF’s are Neocate and Nutramigen AA.
Infant formulas based on soya milk are not suitable under the age of 6 months. They can be used after 6 months of age but there are concerns regarding oestrogen-like properties that could have links with male infertility. Therefore only start soya formulas on the recommendation of your doctor or dietician. Other mammalian milks (goats’ / sheep etc) are not suitable in children with CMA as there is often cross-reactivity between milks, putting them at high risk of allergic reactions to these mammalian milks too.
If the baby is breast-fed, then the mother should eliminate cows milk from her diet completely and take daily supplements of calcium and vitamin D.
In most cases of cows milk allergy, symptoms will resolve within 6 weeks of starting the above formulas or the mother starting a dairy-free diet.
CMA can be managed in primary care and our GPs at ROC Clinic are very happy to help you to manage your baby’s symptoms. We can make a referral to our in-house dietician to help you navigate your way around a dairy-free diet for you or your baby!
