It’s possible. As many as 10-35% of babies with cow’s milk allergy are also allergic to soy. If you are worried, consult your doctor before introducing your baby to potentially allergy-inducing foods such as cow’s milk, soy, eggs, wheat, peanuts, tree nuts and fish.
Cow’s milk allergy is an immune-system response to milk proteins such as casein and whey. Lactose intolerance is when the body can’t digest a milk sugar called lactose. Children with lactose intolerance have insufficient amounts of the enzyme needed to digest this milk sugar. Cow’s milk allergy and lactose intolerance are both caused by milk and share a few symptoms, such as wind, tummy pain and diarrhoea. But unlike cow’s milk allergy, lactose intolerance doesn’t affect the immune system and doesn’t cause allergic reactions such as hives, skin rashes, wheezing or persistent runny noses and coughs.
Now your baby has been diagnosed with cow’s milk allergy, your doctor or specialist will have probably recommended eliminating cow’s milk protein from your baby’s diet.
If you are breastfeeding: because cow’s milk protein can be passed from mum to baby through breast milk, nursing mums may have been advised to follow dairy-free diets until their babies are weaned. Don’t stop breastfeeding though, as breast milk provides the best nutrition for your baby.
If you are bottle-feeding: formula-fed infants may have been advised to switch to a formula that is specially formulated to not cause allergic reactions in babies with cow’s milk allergy. Around 90% of infants with cow’s milk allergy do well with an extensively hydrolysed formula such as Nutramigen with LGG®.
The cow’s milk protein in Nutramigen with LGG® has been broken down or hydrolysed into small pieces so that they are, in most cases, less likely to cause allergic reactions. Rarely, a small number of infants with cow’s milk allergy react severely to cow’s milk protein and may not tolerate an extensively hydrolysed formula. These infants need a hypoallergenic formula made from amino acids, the building blocks that form proteins.
Most children become tolerant to cow’s milk naturally between 3-5 years old. However, you should only introduce your child to foods made with cow’s milk under the supervision of a healthcare professional.
Your doctor may refer you to a paediatric allergy specialist, a paediatric dietitian or a paediatric gastroenterologist (a doctor who specialises in children’s digestive problems). Because some processed foods like bread, cereals and biscuits may contain hidden dairy ingredients, it’s useful to see a dietitian before you start weaning. A dietitian can help ensure that your baby gets the nutrients needed for healthy growth and development while eating a dairy-free diet.