Mum claims her breast milk changed to fight her baby's flu. But is that really possible?

When US mum Paige Peterson’s baby girl Raina was diagnosed with the flu, she was a little confused. Her daughter hadn’t been showing any of the usual flu-like symptoms.

Then when the mum, who breastfeeds, took a look at some of the frozen milk she’d expressed, it all made sense.

Sharing a photo of two different coloured bags of frozen milk side-by-side on Facebook, Paige wrote, “The frozen milk on the left is from two weeks ago. The frozen milk on the right is from this past weekend when her swab [for the flu] came back positive. Notice the change in colour?”

Paige was pointing out that the bag on the right was much more yellow in colour. She concluded that her “breast milk created antibodies to fight off any infections that Raina may have had,” adding she hadn’t given her daughter any medication.

Tens of thousands of Facebook users were quick to praise the wonder that is women’s bodies, but is this really something breast milk can do?

To find out, we spoke to Melbourne-based obstetrician Philippa Costley. She told us that yes, women’s breast milk does change when a baby she’s breastfeeding or herself contracts a virus like the flu.

“While you’re breastfeeding if the mother comes into contact with a virus, the mother will produce antibodies, which then transfer through to the breast milk. If the baby is unwell, the mother is often unwell or in contact with that virus as well,” she told Mamamia.

Listen: The woman behind the new LGBTIQ antenatal classes explains co-breastfeeding. (Post continues.)

Dr Costley, who works in Melbourne’s Royal Women’s Hospital, explained that this is a natural response to a virus and acts to transfer antibodies to a baby to boost their immune system.

“Because the baby doesn’t necessarily have the same ability to produce antibodies as the mother does. It’s the baby getting antibodies without having to produce them themselves.”

Dr Costley added that breast milk will vary in composition and colour for other reasons, such as the woman’s diet and even the time of day. However, she said a colour change as pronounced as Paige’s milk samples was rare.

Of course, not all women can breastfeed, and Dr Costley says they need not be concerned.

“I always say to women, we’re extremely lucky that we live in a country where if you’re unable to breastfeed that we have a good alternative option in formula feeding.”

She also reminded parents it was important they see their GP if their child is displaying flu-like symptoms whether they’re breastfed or not.