Can breast milk change colour – and if it can, is it safe for baby to drink?
That’s what social media is asking after mom Ashlee Chase posted a picture of two breast milk bags she expelled just days apart: one that appears white and the other yellow.
“Top milk is from 3 days ago when a healthy Elliot was nursing,” she wrote. “Bottom is from today, after sick Elliot with a fever comfort nursed all night.”
But according to Frances Jones, co-ordinator of lactation services at B.C. Women’s Hospital and B.C. Women’s Provincial Milk Bank, the colour of Mom’s breast milk can change for a variety of reasons, both good and bad for the baby.
And if Mom was nursing a feverish baby, it’s possible it was due to the illness, she says. In this case, the change in colour is a good thing.
If a baby gets sick, Jones explains that a buildup of Immunoglobulin A is needed in mom’s breast milk, which is used to protect the baby from getting sick. The yellow colour may be because there is a greater buildup of colostrum, which is abundant in those immunoglobulins.
However, it’s natural for Mom’s breast milk to change colour as months go on and baby gets older, Jones says. This is because there is a relationship between Mom’s breast milk and the baby.
At first, Jones says, the milk adapts to the newborn’s needs. Because it’s easy for things like bacteria, viruses and pathogens to transfer from Mom to baby, the milk during that time is designed to coat the baby’s gut with disease-fighting factors.
“When the baby is born, and the mother has what we call colostrum – but it’s the first milk,” Jones says. “That milk is low in fat but high in protein and immunoglobulins, so it’s high in disease-fighting factors. That’s designed that way because a newborn’s gut is like a sieve and it’s very easy for things to move back and forth like bacteria, viruses and pathogens.”
Then as Mom’s more mature milk comes in, the baby’s gut and needs will change as well.
That’s when Moms will often notice their milk turn from a yellowish or orangey colour to a bluish hue, Jones says.
“This is because the milk has changed from colostrum to mature milk,” Jones explains. “And mature milk has a higher percentage of water in it, the volume is obviously bigger and it’s designed for the baby at that stage.”
Another reason for the change in colour may be due to cracked surfaces around the nipple, Jones explains.
“Especially early on is where we see this happen,” Jones says. “Sometimes, the milk will appear brownish or reddish, certainly if they got cracked nipples so it’s obvious where the colour is coming from. There’s a little bit of bleeding into the ducts, but that will often stop within the first week but it obviously colours the milk.”
What Mom eats may also impact the colour of the milk, Jones says, or it could be a reaction to a medication Mom is taking.
If the drug is compatible with breastfeeding then it still might change the colour, Jones explains, but it often won’t be a problem.
And the milk might simply change just based on the time of day, Jones points out, as the composition of the milk will be different at night than it is during the day.
“That’s the beauty of breast milk,” she says. “It evolves to the changing needs of the child.”
And there’s often not a need to worry if there’s a change in the colour, Jones says.
“Most times, it is a normal thing,” she says. “If the mother’s not sure why it’s changing colour, that’s something to check out with someone who has knowledge about that.”
If it’s noticed that some of the pump parts are turning pink or you notice pink in the shower, it’s something to check out, Jones says. This may be due to a bug called Serratia marcescens.
“It can cause some problems if it gets into the mother’s breast as far as pain,” Jones says. “So some of these things can make a baby sick, but with some good information, mothers can deal with it.”