Probiotics have been widely publicised in the media in recent years as the latest ‘wonder cure’. The list of their supposed health benefits seems to be getting longer by the minute as the research continues, with probiotics becoming the selling point of a wide range of products, such as yoghurts and probiotic capsules. And now these ‘friendly bacteria’ made their way into vitamin supplements aimed at breastfeeding women, which is what we will explore in this article.

The making of baby’s gut flora

According to Spanish researchers, human breast milk contains over 700 different types of bacteria. The most common strains include Lactobacillus, Streptococcus, Staphylococcus, Enterococcus and Bifidobacterium. In addition, breast milk contains types of prebiotics known as human milk oligosaccharides (HMOs), which are non-digestible food components used by bacteria to stimulate their growth and activity.

Interestingly, some of the bacteria found in breast milk are considered to be pathogenic, however it is believed that the immune components also present in the milk protect against their harmful effects.

The microbial diversity of breast milk plays a variety of functions in the infant gut, including:

  • Protection against infections
  • Maturation of the baby’s immune system
  • Metabolic role – creating a healthy gut environment

Probiotics have also been used to treat colicky babies after a study showed that the strain Lactobacillus reuteri reduced crying episodes among affected infants. Moreover, there is growing evidence for their role in lowering the risk of allergies, including allergic reaction known as eczema, type 2 diabetes, inflammatory bowel disease (IBD), obesity and coeliac disease.

The colonisation of the gut with probiotics has not been fully understood. Babies have their first contact with gut bacteria when they go through the birth canal. Afterwards, in addition to breast milk, probiotics are also found on the surface of breast skin and in infants’ mouths. The research suggests that there is some bacterial interaction during breastfeeding where microorganisms can be exchanged between an infant’s oral microbiota and the breast milk.

Let’s talk some science

The mechanism through which these bacteria get into the breast milk has been widely disputed among health professionals and scientists. It used to be believed that it was not possible for the probiotic bacteria to pass through from the mother’s gut to the breast milk, and that the colonisation of breast milk occurred through the bacterial contamination from the infant’s mouth during breastfeeding.

But not only has research shown that vertical translocation of probiotics can happen, the latest studies even offered an explanation on the movement of probiotics between the mother’s gut and breast milk. It has been suggested that the gut bacteria are transported via certain types of maternal immune cells known as dendritic cells and macrophages.

Probiotics and mastitis

In some cases, new mums can develop a painful inflammation of the breasts called mastitis. It usually occurs when milk ducts become blocked due to ineffective emptying of the breasts during breastfeeding. The trapped milk can quickly become infected with bacteria entering the breast through sore or cracked nipples leading to an infection that might require antibiotic treatment.

Studies have shown that an oral supplement with lactobacilli strains can reduce the number of pathogenic bacteria and lead to a faster recovery. Probiotics have also been recommended to prevent thrush episodes following the antibiotic treatment.

Which probiotic supplement

If you’re breastfeeding and want to take a probiotic supplement, there are a few options available to choose from. New Chapter Perfect Postnatal is an organic, whole food supplement rich in high quality nutrients, including multivitamin complex and probiotic blend of three bacterial strains to support lactation and meet the needs of new mums. Although quite expensive, the supplement is very highly rated on the other side of the Atlantic and you can buy it in the UK from Amazon or small online vitamin retailers.

Another option is OptiBac Probiotics For Your Child’s Health, which is aimed at infants and children, as well as pregnant and breastfeeding women. The powder contains a blend of prebiotics and probiotic cultures and can be added to cold foods and drinks.

Remember that probiotics, like any other supplement, can have side effects and is not for everyone. Talk to your GP or midwife before taking any probiotic supplement.


    Fernández et al (2013) The human milk microbiota: origin and potential roles in health and disease. Pharmacol Res. 69(1):1-10.

    Jiménez et al (2008) Oral administration of Lactobacillus strains isolated from breast milk as an alternative for the treatment of infectious mastitis during lactation. Appl Environ Microbiol. 74(15):4650-4655.

    Urbaniak C, Burton JP and Reid G. (2012) Breast, milk and microbes: a complex relationship that does not end with lactation. Womens Health (Lond Engl). 8(4):385-98.