If you’ve decided to formula feed, you are then faced with a minefield of options regarding which milk to purchase for your baby. While we can’t go into every brand here, here’s an overview of the main types on offer and their uses and purposes:

Ready-made versus powdered

There are two formats for most formula products: ready-made or powdered. The advantage of ready-made is that it is convenient and easy to feed safely, but its disadvantages are that it’s more expensive to buy and, once opened, needs to be used quickly. The advantage of powdered formula is that it is cheaper, and an open pack can last longer. However, it must be prepared carefully to be safe (see article 25).

Standard infant formula (stage 1, suitable from birth)

This is made from cow's milk that has been adapted to make it more suitable for babies. The formula contains both casein and whey milk proteins, but with a higher percentage of whey to make it more digestible for infants.

It is a highly regulated product, and there is very little difference between brands. There is no evidence that the market leaders provide better nutrition for your baby than the supermarket's own brands.

This standard formula would always be the first choice for a bottle-fed baby. Stick with this formula unless you are advised otherwise by your medical team. This should be the only food they are offered until they are six months of age, when you will start to add complementary foods to their diet. Until they are a year old, any milk given as a drink should be a stage 1 infant formula (from 6 months, cows milk can be given as an ingredient in a meal). Once they are 1 year old, you can give cows milk as a drink.

Other formulas available ‘over the counter’

Hungrier baby formula This type of formula has a higher casein content. Casein is harder for your baby to digest and can cause them some discomfort. There is no evidence that babies are more settled or sleep better when fed this type of formula. This milk shouldn’t be given without consultation with your medical team.
Anti-reflux formula. This milk has been thickened with the aim of preventing your baby from refluxing (bringing up milk after a feed). The milk often needs to be made slightly differently from standard infant formula, so pay careful attention to the manufacturer's instructions when using this formula. These instructions sometimes require the milk to be made at temperatures lower than 70 degrees; the powder still holds the risk of bacterial contamination, which won’t be killed by lower-temperature water, so be especially careful around hygiene when preparing these feeds. Although these formulas are available in supermarkets and pharmacies, it is highly recommended to only use them after consultation with your medical team.
Comfort formula. This formula has had some of the cow's milk proteins partially broken down (hydrolyzed). This is intended to make the milk easier to digest and therefore prevent digestive discomfort, as seen in colic and constipated babies. However, there is no evidence that this is the case. Again, only use this formula after consulting with your medical team.
Lactose-free formula. This formula is designed for babies who are lactose-intolerant. This means that they cannot absorb lactose (a naturally occurring sugar in dairy products). This is a very rare condition in babies and should be brought to your medical team’s attention if you believe it to be the case for your baby. Lactose is an important milk sugar in all mammalian milks, and lactose-free formula should not be given without medical supervision.

Prescription formula

If your baby has been diagnosed as being allergic to cow’s milk, your doctor will prescribe you a hypoallergenic formula. These formulas are available on prescription only. The hypoallergenic formula is made with fully hydrolysed (broken down) proteins, which can impact the taste. Some babies will take time to get used to this formula. If your baby has CMPA, the comfort formula won’t be suitable as the proteins are only partially broken down.

Goat milk infant formula

There are some infant formulas that have been based on goat’s milk rather than cow’s milk. These are also highly regulated and have been produced to the same nutritional standards as regular cow’s milk formula.

It is important to note that goat’s milk formula is not any less likely to cause an allergic reaction in babies than cow’s milk formula. The milk proteins in cow's milk and goat's milk are very similar, and a baby who has CMPA (cow milk protein allergy) is also highly likely to be allergic to the proteins in goat's milk.

Stage 2 (from 6 months) formula

There is no nutritional need to move onto a stage 2 formula at six months. These formula milks exist because the World Health Organisation doesn’t allow the marketing of first infant milks, and this is a ‘loophole’ that allows formula companies to run marketing campaigns. Take a look the next time you see a formula ad; the branding looks identical, but you’ll see that the box has a number 2 on it, so the company is technically staying within the guidelines. Research has shown no benefit to moving to the stage 2 formula, and as it is less strongly regulated than the stage 1 formula, it’s recommended to stay with stage 1 for a year.

Stage 3 (toddler's milk)

These milks are advertised as an alternative to standard cow's milk for children over a year of age. They are usually more expensive than regular milk, and there is no evidence to suggest that they provide any additional nutritional benefits. It is therefore preferable to give standard whole milk to toddlers. Semi-skimmed milk shouldn’t be used until they are at least 2 years old.

Soya formula

This is a formula that is only suitable for 6 months, and even then, only under medical supervision. This “milk” is not made from milk at all, but from soy beans. There have been some concerns about the phytoestrogens that are naturally found in some plants, including the soy bean plant. There are some similarities in the chemical structure of phytoestrogens and oestrogen (the female reproductive hormone). This has led to concerns regarding a baby’s reproductive development when they drink only a soy-based formula.

Milks that are not suitable as infant formulas

In addition to the baby formulas above, some parents are recommended by friends and families to give other forms of milk. However, these are not suitable for feeding babies. You should never give the following types of milk to a baby under 1 year:

Condensed milk.
Evaporated milk.
Dried milk.
Other types of drinks are known as "milks", such as soya, rice, oats, or almond drinks.
Cow, goat, or sheep milk as a drink (but it's fine to use it in cooking as long as it’s been pasteurised).

What formula should I use?

For our Baby Feeding Journey, Unii Expert Wendy Lever advises what formula you should use.