If you or a loved one has ever pumped breast milk, you may have noticed the colour of the liquid isn’t always identical from one session to the next. But have you ever wondered why?
“There are many factors that can affect the color of someone’s breast milk,” Johanna Sargeant, an international board-certified lactation consultant, tells HuffPost. “One of the amazing things about breast milk is that it is dynamic, constantly changing to adapt to your child’s needs throughout the feed, the day and the entire duration of your breastfeeding journey.”
She emphasises that the milk from a morning pumping session can look different from what’s expressed during an evening session, and milk from two days postpartum will likely differ from what you see two months or even two years later.
“Most of the colour differences in these situations are due to changes in fat and water content of the milk, though there are a whole rainbow of other colours that can pop up too, depending on your diet and your own biology,” Sargeant adds.
Indeed, the colour of breast milk tends to change based on what foods or medications the parent is consuming. However, that generally doesn’t mean its quality has changed – so don’t immediately throw out milk that differs from previous pumping sessions.
“Milk can change colours in the early days as it transitions from colostrum to mature milk,” notes international board-certified lactation consultant Leigh Anne O’Connor. “In most cases it is perfectly safe for babies and toddlers to consume milk that is colored. When breastfeeding directly, the colour of milk is not seen so it is a nonissue.”
Although there’s usually nothing to be alarmed about, it’s still interesting to consider the reasons for different hues of breast milk. Below, lactation experts break down the different colours and potential explanations.
Yellowish
“The very first milk that your baby gets is also called colostrum ― though it is, indeed, a type of milk,” Sargeant explains. “This condensed breast milk is often bright yellow or orange in colour, which comes from high levels of beta-carotene, which is essential for cellular health and is a precursor to vitamin A.”
As you progress beyond those early postpartum days, your mature milk can appear yellowish at times as well.
“Frozen milk may take on a yellowish colour, which is not a sign of spoilage,” says Susan Mocsny Thomas, a registered nurse and professional liaison department administrator with La Leche League Alliance.
A slight yellow shade might also be an indication that the fat content of the breast milk is higher. During a pumping or feeding session, the first milk that comes out is known as the foremilk, and the milk that follows is called the hindmilk. While the foremilk is generally higher in lactose, hindmilk is fattier and thus more likely to look yellowish.
As noted previously, the parent’s diet can have an impact on the colour as well.
“We know that eating foods high in beta-carotine, such as carrots or sweet potatoes, can also give your milk a more yellow hue,” Sargeant says.
Greenish
“Breast milk can change based on what you eat, so if you eat a lot of green veggies, drink an energy drink with green dye, or take a lot of herbal supplements, it can take on a greenish hue,” says parenting writer and international board-certified lactation consultant Wendy Wisner.
Indeed, the artificial colouring in sports drinks and other beverages can give your milk a variety of tints, including green. The same goes for consuming seaweed, spirulina or certain multivitamins. Medications like nifedipine, which is used to treat high blood pressure and chest pain, may also have this emerald effect on breast milk.
Thomas points to breast milk colour research from the authoritative reference guide, “Breastfeeding and Human Lactation.” As the text states, “Propofol (Diprivan), blue-green algae, and iron supplements have been reported to give human milk a green hue.”
Blueish
As with the green hue, breast milk may appear more blueish if a parent drinks a blue energy drink or other artificially blue beverage. However, there are other more common reasons.
“Milk that is very clear and may have a slight blue tinge is usually milk that has a higher proportion of water, protein and sugars, with a lower fat percentage,” Sargeant explains. “The blue tint is thought to come from the casein, the protein found in the milk.”
She notes that blueish milk often comes from very full breasts producing an overall larger volume of milk. So if you haven’t nursed recently, your breast milk will likely take on that clearer, almost blue colour when you first express (and eventually look thicker and more yellowish).
“Here, some of the fat globules stick to the sides of the milk ducts, and are only released later on in the feed,” Sargeant says, highlighting the difference between the foremilk and the higher fat-content hindmilk.
“Keep in mind that this more clear milk is filled with everything essential for baby’s growth, including enough fat, along with stem cells, antibodies and many other amazing things,” she emphasises. “So this kind of milk is in no way ‘worse’ than the creamier, fattier, whiter milk that you may see coming from emptier breasts, or from later on in a pump.”
In recent years, there have been many viral social media posts claiming that the colour of breast milk can change due to antibody production in response to a baby’s illness. Although it’s certainly possible, there’s no published research to support the antibodies theory. Instead, some have speculated the color may appear different due to changes in the baby’s feeding pattern as a result of the sickness.
Reddish Or Pinkish
Some medications, like rifamycin antibiotics and the leprosy treatment clofazimine, have been reported to give breast milk a pink or red tint. Food dyes and certain foods may have the same effect, especially when eaten in large quantities.
“Beets can turn it reddish or pinkish,” Wisner says. “Other reasons for reddish milk can be from blood – cuts on the nipple that have mixed with milk.”
Before you panic upon seeing blood in your milk, understand that it could be the result of minor external or internal injuries to the nipple or milk ducts. Although it may be alarming to look at, your breast milk remains safe for your baby.
“An open wound in the nipple may release some blood into the milk and create pink milk, or a burst capillary inside the breast can result in a deeper red colour of milk,” Sargeant says. “While it’s clear that it is fine to feed your baby milk that has some blood in it, beware that it may make your baby’s poop darker, and can be harder on their digestion. If you are worried and are planning to discard your milk, you can leave your milk in the fridge for a few hours and the blood cells will often settle towards the bottom of the bottle.”
In most cases, reddish or pinkish breast milk is not an issue, but there are a couple of situations to pay attention to.
“If you are seeing blood frequently and can’t figure out a cause, you should see your health care provider, because rarely, blood in the milk can be a sign of breast cancer,” Wisner says.
She and Sargeant also urge parents to look out for a persistent pink colour, which may indicate a bacterial infection.
“There is really only one colour where you need to be a little more aware, and that is if your milk has become fluorescent pink,” Sargeant says. “I’m talking 80s style bike-shorts pink. In this situation, it could be a sign of the presence of a particular bacteria, serratia marsescens, which is worth ruling out with your doctor.”
Brownish Or Blackish
Brown or black may feel like even more troubling colours to see in your breast milk, but rest assured, there are normal explanations for these hues.
“Something called rusty pipe syndrome can make your milk look brownish,” Wisner explains, noting that it’s common in colostrum. “Rusty pipe syndrome happens during the first few days of nursing, as your ducts expand, and a little blood is released.”
As always, just monitor the situation to see if the appearance changes over time, as it likely will once the residual ductal blood is gone. Talk to a health care professional if the brown colour persists, however.
When it comes to black breast milk, medicine is the likely culprit.
“The antibiotic Minocin has been known to change breast milk to black,” O’Connor notes.
If you’re prescribed a minocycline antibiotic or really any medication, ask your doctor if it’s safe to take while breastfeeding.