Formula Milk: A Feeding Guide

Maybe you already plan to feed your baby partly or exclusively with formula milk, or perhaps you’re still gathering the info you need to make an informed choice, or perhaps you had planned to breastfeed but now would like to switch to or supplement with formula. Either way, read on to find out more, including how much formula your baby needs, how often to feed your little one and which is the best formula milk for your newborn.

What Is Formula Milk?

Formula milk, also known as infant formula or sometimes just ‘formula’, is a substitute for breast milk that can be used either as an alternative to breastfeeding, or as a way of supplementing it. Formula is usually (but not always) made from cow’s milk, which is specially processed to make it suitable for babies to drink. Remember: Children under 1 year old can’t digest unprocessed cow’s milk. Formula milk contains all the nutrients your baby needs to grow and develop, but it does lack some of the additional health benefits of breast milk, such as protection from infection. How you decide to feed your little one is a personal choice that depends on many factors unique to you. If you do plan to use formula, however, you still might want to express your first milk – known as colostrum – and feed this to your baby for the first few days before introducing the formula. Colostrum is not only packed full of nutrients; it has lots of other health benefits – such as boosting your baby’s immune system, improving digestion and helping regulate blood sugar.

Choosing the Best Formula for Your Baby

When you first walk into a shop or pharmacy that sells formula, you might find the range of boxes and packets on display a bit bewildering at first, with so many different brands and types of infant formula on offer.

Don’t let this confuse you though: Just check the label carefully and keep in mind that newborns need what is known as ‘first infant formula’ (usually marked ‘suitable for newborns’) until at least 6 months of age, unless your doctor or midwife advises otherwise.

Experts also advise sticking to this type of formula until your baby is at least around 1 year old, when you can start giving your baby (pasteurised) cow’s milk to drink.

Ready-to-Feed or Powder?

Infant formula milk comes in two forms:

• Powdered. This is usually the most economical to buy and needs less room to store. The catch? You do have to make it up (by mixing it with water) before using it. Formula milk powder is not sterile so you need to make up each feed just before use.

• Ready-to-feed. This is formula that is already in liquid form, sold in sealed cartons or plastic bottles. It’s sterile, so it can be stored and used straight out of the bottle (although the feeding equipment must be sterilised before each use). The downside is that it can be more expensive, takes up more cupboard space and goes off quickly once you open the bottle.

Alternative Formulas

First infant formula is usually best for your baby, but in rarer cases your doctor or health visitor may suggest an alternative.

Although most of these types are available ‘off-the-shelf’ in supermarkets or pharmacies, many are only recommended for use under medical supervision. Always check with your midwife, health visitor or doctor before switching from first infant formula, especially in the first six months.

Examples of alternative formulas include:

• Anti-reflux (‘staydown’) formula. This type of formula milk is thicker, to help prevent severe cases of reflux or gastro-oesophageal reflux disease (GORD) and may be recommended to you if other measures (such as frequent burping, upright feeding) don’t seem to be working. This kind of formula is only recommended for use under medical supervision.

• Lactose-free formula. Some babies have difficulty digesting lactose (the natural sugar found in milk). Lactose intolerance is not an allergy, but it may cause symptoms like colicky crying, diarrhoea, tummy ache and wind. Lactose-free formula could help; but should only be used under medical supervision Tell your health visitor or doctor if you suspect your baby has a lactose intolerance.

• Hypoallergenic formula. If your baby is diagnosed with an allergy to cow’s milk, your doctor can prescribe a special infant formula with fully hydrolysed (broken down) proteins.

• Soya formula. Made from soya beans, this is sometimes recommended as an alternative for babies with a cow’s milk allergy. However, there are concerns about whether the phytoestrogens (similar to the hormone oestrogen) in soya beans could affect babies’ development. Only use soya formula if your doctor or health visitor has prescribed or recommended it.

• Goat’s milk formula. This is produced to the same nutritional standards as cow’s milk formula, but from goat’s milk. It can’t be used as an alternative for babies with a cow’s milk allergy though, because the proteins found in goat’s milk are very similar to cow’s milk protein.

• Comfort formula. Comfort formula contains partially broken-down (hydrolysed) proteins. Its claim is that this makes it easier to digest – alleviating problems like colic or constipation – although there is no medical evidence to back up this claim so it might be best to talk to your doctor or midwife first if you are concerned about your little one’s digestion and you’re considering this type of formula.

• Formulas for babies older than 6 months. These include ‘follow on’ formula, ‘good night milk’ and ‘growing up’ or ‘toddler milk’ (for babies older than 1 year). Experts usually advise sticking to first infant formula until your little one is fully weaned, so it’s best to ask your health visitor or doctor for personalised advice before trying out any new type of formula marketed for older babies or toddlers.

How Much Formula Does Your Baby Need?

Your newborn baby only needs small amounts of formula in the first few days – after all, his or her tummy is still very small, but it’s growing all the time.

Just to give you an idea how small your newborn’s stomach is, and how fast it grows:

• On day one it’s about the size of a cherry and holds around 5-7 millilitres

• On day three it’s the size of a walnut, with room for 22-27 millilitres of formula or breastmilk

• After one week it’s grown to the size of an apricot and can hold about 45-60 millilitres at a time

• After one month your baby’s stomach is about the size of a large egg, with a capacity of 80-150 millilitres.

From after the first week until around 6 months old (when your baby starts weaning), your little one may need around 150 to 200 millilitres of formula milk a day for every kilogram of body weight.

So, for example, a 1-month-old baby weighing around 4 kilograms might need between around 600 and 800 millilitres of formula a day, spread over several feeds. Here are some more examples of how much formula your baby may need per day based on different bodyweights:

All babies are different, and so are their appetites! In practice, though, once your child settles into a feeding pattern and you get to know his or her feeding cues, you’ll probably find it natural to increase the quantity of formula gradually in response to demand.

How to Tell When Your Baby Is Full

This means it is possible to overfeed your baby with a bottle, so it’s important to recognise when he or she is full. A good way of doing do this is called ‘pacing’:

• Let your baby pause every few sucks – gently withdraw the bottle and see if he or she wants to stop

• This could also be a good time to burp your baby, especially if he or she spits up formula, or seems windy or uncomfortable

• Only start feeding again if your baby draws the teat back into his or her mouth

• Don’t push the teat into your baby’s mouth or try feeding if your baby turns his or her head away.

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How Often Should Your Newborn Feed on Formula?

Feed your baby whenever he or she shows signs of being hungry. These signs are known as ‘feeding cues’, and they can include:

• Moving the head from side to side (rooting)

• Lifting or bobbing the head

• Sucking on a finger, fist or blanket (or anything else within reach)

• Drooling

• Licking or smacking the lips

• Crying (this is a late sign – it’s often easier to feed your baby if you can spot the earlier feeding cues in time).

How to Be Sure Your Baby Is Getting Enough Formula

Rather than strictly following a chart to decide how many ounces or millilitres a baby should eat at a given age or weight, experts advise feeding ‘on demand’ in response to the feeding cues listed above.

As long as your little one is gaining weight normally and producing enough wet nappies, you can be pretty certain he or she is getting enough formula.

From the first few days after being born it’s normal to see around six heavy nappies, soaked with pale or clear urine, every day.

Your baby will usually be weighed a few times in the first 10 days after birth, and then once a month after that – at monthly health and development reviews – until the age of 6 months.

During the health and development reviews your health visitor and/or doctor will use growth charts to keep track of your baby’s growth and weight gain.

These visits are also a great opportunity for you to ask questions or discuss any concerns you might have. But if you’re ever concerned about whether your baby is eating enough, you can always turn to your midwife or doctor between the scheduled visits.

How to Make Up a Feed

Always make the formula just before you need to use it and don’t reuse any formula milk that’s been left over from a previous feed.

Make sure the surfaces you’re using are cleaned and disinfected, and the feeding bottle and accessories are also cleaned and sterilised.

1. Boil at least 1 litre of fresh tap (not bottled) water in a kettle, then leave it to cool for no more than 30 minutes (so it stays above 70 degrees Celsius – this is hot enough to kill any germs that might still be in the bottle).

2. Stand the bottle on the disinfected surface, and – following the manufacturer’s instructions – pour the correct amount of hot water from the kettle into the bottle. Be careful to check the water level.

3. Again, following the manufacturer’s instructions carefully, use the scoop supplied with the formula to add the powder to the water in the bottle. Don’t forget to level off each scoop of powder with a clean, dry knife or the provided leveller.

4. Insert the teat into its retaining ring (following the instructions supplied with the feeding bottle) and screw it on.

5. Put the cap over the teat and shake the bottle until all the powder is dissolved.

6. Cool the bottle under cold running water (with the cap on) or leaving it to stand in a bowl of cold water.

7. Test the temperature of the formula by dripping some onto the inside of your wrist – it should be warm or cool, but not hot.

Storing and Transporting Formula Milk

Powdered formula milk isn’t sterile, so only make up a feed just before using it and throw away any formula that’s left over after a feed.

If you need to feed your baby while you’re out and about, it helps to take

• the amount of formula powder you need for a feed, measured out into a small, clean and dry, airtight container

• a clean vacuum flask containing just-boiled tap water (the flask will keep the water at over 70 degree Celsius for several hours)

• an empty, sterilised feeding bottle with the teat, retaining ring and cap.

Transporting and Storing a Made-Up Feed

Sometimes, transporting a made-up feed might be the only option (for example, if you need to take a feed to nursery school). In this case, make up the formula at home, cool it in cold water and then cool it further in the back of the fridge for at least an hour before transporting it.

Made-up formula stored in a fridge should be used as soon as possible, but within a maximum of 24 hours.

Move the made-up formula from the fridge to a cool bag with ice packs just before leaving the house and use it within four hours (or two hours if you don’t have ice packs).

A Quick Guide to Bottle-Feeding Your Baby

Feeding isn’t just about nutrition – it’s a chance for social interaction and bonding. Sit comfortably and make eye contact. Enjoy these moments of closeness with your baby.

Just because you’re bottle-feeding, doesn’t mean you and your baby have to miss out on plenty of skin-to-skin contact. Holding your little one close against your skin is not only good for bonding, it also has a calming effect and helps regulate your baby’s breathing and body temperature.

Here’s a brief guide to bottle-feeding your baby:

• Hold your baby upright in a comfortable, neutral position. Your infant shouldn’t need to tilt or turn the head to reach the bottle

• Hold the bottle almost horizontal to the ground, tilted just enough to fill the teat with the formula

• Brush your baby’s lips with the teat, and your child will usually open his or her mouth wide and put out his or her tongue

• Help your baby to draw the teat into his or her mouth

• Check for air bubbles rising up in the formula. If no bubbles appear, a vacuum may have formed in the teat. This can stop the formula flowing. Break the vacuum by gently moving the teat sideways in your baby’s mouth

• If your infant seems restless or uncomfortable, have a ‘burping break’ before seeing if he or she wants any more more milk

• Never feed your baby lying down, to avoid the risk of choking. Babies should never be left unattended while feeding or allowed to fall asleep with a bottle in their mouth.

The Bottom Line

We hope this quick guide takes some of the mystery out of formula milk and bottle feeding. And remember, the secret ingredient isn’t in the bottle: The love and care you put into feeding and caring for your baby is what makes those feeding sessions so special for you and your little one.

How we wrote this article

The information in this article is based on the expert advice found in trusted medical and government sources, such as the National Health Service (NHS). You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.