Deciding whether to breastfeed or formula-feed? Well, for babies to be resistant to infections, their tiny digestive systems must be colonised with friendly, essential bacteria. And one way to do that is to breastfeed: a brand new study now shows that the healthy bacteria in the mother’s gut can reach her baby via breastfeeding.

Study details

The researchers performed a variety of laboratory techniques including DNA tests on the breast milk of seven healthy mothers and their exclusively breastfed babies within their first month of life.

They also analysed faeces samples to identify the kind of bacteria present in both the mothers’ guts and their babies’.

Study findings

“We are excited to find out that bacteria can actually travel from the mother’s gut to her breast milk,” declared study lead author Professor Christophe Lacroix from the Institute for Food, Nutrition and Health, ETH-Zurich, Switzerland.

The scientists discovered identical types of Bifidobacterium breve and several kinds of Clostridium bacteria in breast milk, and maternal and/or infant faeces. These bacteria are essential for colonic health and for optimal immune system development as they help prevent over-colonisation of potentially harmful bacteria like E.Coli and Streptococci in the baby’s gut. The researchers believe that these bacterial strains can promote an optimum nutritional balance in the baby’s colon, thus helping to prevent intestinal complications.

“A healthy community of bacteria in the gut of both mother and baby is really important for baby’s gut health and immune system development,” explained Professor Lacroix.

“We’re not sure of the route the bacteria take from gut to breast milk but, we have used culture, isolation, sequencing and fingerprinting methods to confirm that they are definitely the same strains,” he added.

The study was published in Environmental Microbiology, a journal of the Society for Applied Microbiology (SfAM). These findings could help enhance formula milk so that it can have properties similar to those of natural milk.

Breastfeeding recommendations

The WHO, UNICEF and several international nutrition committees strongly advise mothers to exclusively breastfeed their babies for at least 6 months. Thereafter, you can continue breastfeeding up to age two or beyond but your baby will need complimentary nutrition.

Here’s what these organisations recommend:

  • Start breastfeeding your baby within her first hour of life;
  • Breastfeed exclusively – do not give your baby any extra food or drink during the first six months;
  • Breastfeed your little one on demand – as often and whenever she wants;
  • Do not use bottles, teats or pacifiers.

Proven benefits of exclusive breastfeeding for you and your baby

Studies show that breastfeeding can:

  • Decrease infant death caused by common illnesses like diarrhoea or pneumonia;
  • Speed up recovery after an illness;
  • Prevent onset of food allergies and celiac disease;
  • Halt atopic eczema (a skin condition);
  • Prevent asthma;
  • Decrease predisposition to obesity and related diseases like type 2 diabetes later in life;
  • Create a unique bond between mother and child – this promotes healthy growth and development;
  • Reduce risk of breast and ovarian cancers;
  • Diminish likelihood of postpartum depression.

Help and support

If you’re having trouble breastfeeding, feel uncomfortable or sore; do not hesitate to seek support from midwives or lactation consultants. Visit NHS Breastfeeding Help and Support for a list of useful websites and helplines.


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