What diet changes are needed?

"I gave my daughter her first bottle of extensively hydrolysed formula in the evening, by the next morning she had a normal baby's bowel movement and everything improved from there onwards."

Alice Williams, Holyhead

Once your doctor has diagnosed your baby with cow’s milk allergy, you’ll be able to start managing it properly and seeing changes for the better.

It’s possible to prevent the signs and symptoms of an allergic reaction very effectively by removing cow’s milk protein from your baby’s diet (see more details about cow’s milk proteins below). This is the same as the elimination diet that your doctor may request during the diagnosis process.

It’s important that you don’t put your baby on a cow’s milk protein-free diet without the advice and supervision of a healthcare professional – so make sure you’ve discussed it with them first. How you switch your baby onto an appropriate diet depends on whether you’re breastfeeding or formula-feeding.

Which foods contain cow’s milk protein?

Breast-fed babies

Breast milk provides the best nutrition for your baby, so it’s important to continue breastfeeding if you’re already doing so. However, your doctor or dietitian might ask you to remove cow’s milk protein-containing products from your own diet, as they could be passed onto your baby through your breast milk. A dietitian would be able to advise you on suitable alternatives to make sure that your diet is not deficient in nutrients.

Good to know
Soya formulas are not recommended as a substitute for cow’s milk, as some babies with cow’s milk allergy may also be allergic to soya. What’s more, soya formulas are not usually recommended for babies aged 6 months and under, and should not be the first choice in older babies, unless advised by a healthcare professional.

Formula-fed babies

Standard baby milk formulas contain cow’s milk proteins, which are recognised by the immune system of babies with cow’s milk allergy as a threat, and this triggers an allergic reaction.

If you’re bottle-feeding, you’ll need to switch your baby onto a special hypoallergenic formula designed for babies with cow’s milk allergy. These formulas don’t contain whole cow’s milk proteins and there are different types available, two of which are: extensively hydrolysed formulas; and amino acid-based formulas.

Extensively hydrolysed formulas

The cow’s milk proteins in an extensively hydrolysed formula have been broken down into small pieces, so they’re unlikely to be recognised by the immune system. This means that they are less likely to cause an allergic reaction in the majority of babies with cow’s milk allergy. In fact, extensively hydrolysed formulas are effective in at least 90% of infants with cow’s milk allergy.

 “After starting my baby on an extensively hydrolysed formula, she was like a different baby... I no longer had to see her in pain any more.”

Alice Williams, Holyhead


Amino acid-based formulas

Amino acid-based formulas don’t contain any protein chains at all – they only use the basic building blocks of protein – amino acids. If your doctor has diagnosed your baby with severe cow’s milk allergy or multiple allergies, or you’ve tried an extensively hydrolysed formula recommended by your healthcare professional and still notice symptoms, you may need to try an amino acid-based formula. 


Find out more about extensively hydrolysed and amino acid-based formulas and why they’re more suitable than other types of cow’s milk alternatives.