New guidance on powdered infant formula preparation

Infant formula is an essential product for infants aged under 12 months who are not breastfed. It exists in two varieties: ‘ready to feed’ liquid and powdered formula. Unlike ‘ready to feed’ milk, powdered formula cannot be made sterile. The correct preparation of the powder, using water boiled in a kettle and still at least 70ºC, is vital to kill any bacteria present. As babies have under-developed immune systems, there is a risk of infection from any remaining bacteria.

Dr Aimee Grant, a Senior Lecturer in Public Health at Swansea University, led a team of academics, health professionals, and third-sector experts to explore the safety of at-home infant formula preparation. The project was funded by the Citizen Science for Food Standards Challenges programme, a collaboration between the Food Standards Agency, BBSRC and the Economic and Social Research Council.

Her project worked with parents to co-design the study using “citizen science”, including asking parents to test the temperature of the water used to prepare their infant formula.

It was found that many infant formula preparation machines tested (85% of 74 machines) did not appear to produce water that would be hot enough to kill all harmful bacteria, which could present a risk to infant health. The research findings were communicated to the NHS and in December 2023 their online guidance for formula feeding was updated to include ‘Using a baby formula preparation machine’. This guidance may help parents provide safer formula for their babies.