Important notice: This article contains information about infant formula and is general in nature. For specific advice, or if you are considering bottle-feeding, always consult your doctor, midwife or healthcare professional for advice about feeding your baby. Introducing infant formula either partially or exclusively may reduce the breast milk supply and is difficult to reverse should a mother change her mind. More information can be found here.

If you are new to infant formula, or perhaps a veteran in using formula, you may be wondering what the difference between different infant formula ‘Stages’ are and when it the right time to transition your baby from one to another.

Infant formulas made from cow’s milk contain two types of cow’s milk protein, whey and casein. These are both found naturally in cow’s milk. It has been found that whey protein is easier to break down and digest than casein protein.

Stage 1 Infant Formula

• Stage 1 Formula is formulated for the needs of newborn babies. It will usually made of majority whey protein (the one that’s easier to digest) in order to be kinder to a newborn baby’s gastrointestinal tract.

Stage 2 Follow-On Formula

• Stage 2 formulas are recommended for children aged 6-12 months. These formulas are typically formulated with majority casein protein which is believed to take longer to break down and digest, and some people believe, this higher volume of casein is good for ‘hungrier babies’ as the casein will keep them fuller for longer.
• Stage 2 Formulas also have a bit more iron added to them than Stage 1 formulae as from 6 months of age, a baby’s requirement for iron increases (they get their initial supply of iron from their mum at birth but this starts to deplete at about 6 months of age – which is why iron rich solids are recommended from 6 months).

Stage 3 Toddler Milk Drink

• Stage 3 formula is marketed as being suitable for toddler up to 3 years of age.
• Unlike Stage 1 and 2 formula, Stage 3 formula is not designed to be nutritionally complete to meet all of the nutritional needs of a toddler. It is available for use by toddlers who’s solids diet is not yet nutritionally complete enough to meet their needs for growth and development.
• The two main nutrients of note in there are iron and calcium. These are present in much higher doses in Toddler milk than they are in Stage 1 or 2 formulae so provide good supplementation for these nutrients particularly.

So… these are the formulae and when they are marketed for use but when should you actually transition from one to another??

The answer is that you can stick with a Stage 1 formula until your child is 12 months old if they are tolerating it well. If you think they seem really hungry at 6 months of age, you could transition them to a Stage 2 formula, or you could start them on solids.

Most toddlers do not need a Stage 3 milk but as mentioned above, for those who have not yet got the full balance of food groups in their diet, it can be a handy supplement to go alongside their diet while they continue to work on building their dietary variety.

This article is designed to provide general advice for parents and guardians. For specific health advice, please consult with your child’s healthcare practitioner.