Formula feeding: What's in infant formula milk?

Here we look at what’s in infant formula with information on the differences between brands.

What's in formula milk?

Infant formula is usually based on processed, skimmed cow’s milk. Added ingredients include vitamins, fatty acids and prebiotics (carbohydrates that can stimulate the growth of ‘good’ bacteria in the digestive system). You can see a full list of contents on the packaging for infant formula milk for babies.

Why are there different types of infant formula?

Most brands in the UK are ‘whey dominant’ or ‘casein dominant’ and this refers to the proteins in the formula. While both can be used from birth, ‘whey dominant’ is usually recommended for new or younger babies because whey proteins are easier for them to digest.

‘Casein dominant’ formula is labelled for ‘hungrier’ babies because the ‘tougher’ proteins may lead to longer gaps between feeds, theoretically reducing how much milk a baby needs to drink. In practice, offering ‘hungrier’ formula may make no difference, and the calorie value of ‘whey dominant’ and ‘casein dominant’ is the same.

You can’t always tell from the brand name which is which, so read the packaging for more information.

Which is the best brand of infant formula milk?

It can be confusing when there are so many different brands all making various claims and with different ingredients. There’s no independent comparison of the quality of different formula and all types have to meet the same legal requirements to support growth and nutrition. For a healthy, full-term baby, it really doesn’t matter which brand you choose.

Can I change the formula my baby has?

Traditionally, parents were advised to stick to one brand, but there’s no good evidence that changing does any harm. You can try different formulas to see which your baby might prefer in case the small variations between them have an effect. A few babies may do better with a special formula instead of the regular kind but this needs medical advice.

Does formula make a difference to my baby’s health?

When formula is prepared safely, most babies who have it stay healthy and grow well. Research on large numbers of babies shows that breastfeeding decreases the risk of infections and other illnesses but it isn’t possible to predict what effect the use of formula has on individuals.

If you continue to breastfeed as well as feed formula, your breastmilk will continue to offer benefits to your baby. 

Can I use formula and continue to breastfeed?

Milk supply is generally driven by frequent, effective breastfeeding. Giving your baby formula can have an impact on this, because it may mean your baby breastfeeds less often, and therefore you make less milk. Read our article about mixed feeding to find out more. You may also find it useful to talk through your options with your midwife, health visitor or breastfeeding counsellor.

Further information

NCT supports all parents, however they feed their baby. If you have questions, concerns or need support, you can speak to a breastfeeding counsellor by calling our helpline on 0300 330 0700, whether you are exclusively breastfeeding or using formula milk. Breastfeeding counsellors have had extensive training, will listen without judging or criticising and will offer relevant information and suggestions. You can also find more useful articles here.