Formula feeding

Formula choice and preparation

Advice for formula-feeding families adapted from First Steps Nutrition Trust:

No powdered infant formula is sterile. Follow the NHS instructions for making up formula which, critically, includes using water at a temperature of no less than 70°C to kill any potential bacteria which may be present.

All infant formula brands are interchangeable regardless of price differences. For healthy, non-breastfed or partially-breastfed babies between birth and 12 months of age, any infant formula is suitable because the law requires that they all comply with the same nutrition composition standards. Choose one based on cows' or goats' milk, avoiding 'hungry baby', anti-reflux and lactose-free.

Follow-on formula marketed for use from 6-12 months could be harmful for babies under 6 months old. It is also unnecessary for a baby from 6-12 months of age where infant formula is available.

Only use a specialised milk on the advice of a health care professional. Formula marketed as a "food for special medical purposes" may cause harm or lack evidence for effectiveness.

'Growing up' or toddler milks should not be given to infants under 12 months of age as they could be harmful for them. These products are not subject to any laws with respect to their composition, marketing or labelling and may contain a lot of sugar as well as being more expensive than cows' milk.

Using a kettle to prepare formula

The safest way to prepare a bottle of formula is to use water that has been boiled in a kettle and is still at least 70°C. This helps prevent serious illnesses from Salmonella and Cronobacter.

• Wash and sterilise bottles and teats every time - old formula is an ideal environment for bacteria to grow.
• Bacteria can already be in formula before you open it - make feeds with water above 70°C to kill bacteria.
• If you fill a kettle with 1 litre of water and boil it, it should stay above 70°C if used within 30 minutes.
• Clean and disinfect surfaces every time to kill bacteria.
• Wash your hands every time - bacteria from your hands can transfer to the scoop and powder and live for over a week.

Read more at First Steps Nutrition Trust.

Using a formula preparation machine

Despite marketing claims, formula preparation machines or devices often do not deliver water hot enough (at least 70°C) to kill any bacteria that may be in powdered infant formula.

If you do have a formula preparation machine, check the temperature of the water dispensed using a food thermometer. Always do this separately to making a bottle, as the themometer can contaminate the water. If the temperature is below 70°C, use a kettle instead to make up bottles, and report to the manufacturer of the formula preparation machine.

Read more about making up bottles of infant formula from hot taps and baby kettles (pdf, November 2019) from First Steps Nutrition Trust.