Colors of breast milk: what each shade indicates

If you are asked to think about breast milk, you probably instinctively imagine it as white. And, indeed, most of the time it is like that. However, like a living fluid, it changes its composition (proteins, amino acids, hormones, vitamins, minerals, carbohydrates, fatty acids…) to adapt to the baby’s requirements. Consequently, its appearance is also modified, and can acquire different shades. Inma Mellado, certified breastfeeding consultant (IBCLC) and president of the Spanish Association of IBCLCs explains: “Unlike cow’s milk, which is much whiter, human milk usually has a more whitish and grayish color; cream-yellow if it is colostrum.”

For her part, lactation consultant and clinical psychologist Purificación Barroso adds: “The milk following colostrum, the transitional milk, continues to be creamy, but not as dense, and has a more creamy color. Mature milk, which is what we have for the duration of our breastfeeding, usually presents different shades of white, such as a light blue, more yellowish… In principle, all shades within white are normal.”

Additionally, although not necessarily, it can also change throughout the same shot: “It depends on many factors such as the frequency of the shots. At some times it may be more whitish (due to a greater presence of casein) and at other times a little more creamy due to a greater presence of fat globules, but the order of this coloration may vary,” explains Inma Mellado.

But what happens when breast milk turns green or black, for example? Well, it means that maternal diet, physiological causes, taking certain medications or certain pathologies can give it other colors. What’s more, “when our baby is sick, the composition of the milk also changes to adapt to these new needs and, therefore, its appearance,” clarifies Purificación Barroso.

In short, in general there is no need to worry about changes in the shades of our milk; Inma Mellado makes it clear that: “The color of breast milk does not make it more or less healthy because it is perfect in itself.” However, it is advisable to know the colorations that may be abnormal and ensure that there are no problems for successful breastfeeding.

4 colors of breast milk and their causes

Although we normally do not notice the color of our milk, unless we express it (or there are some remains in the baby’s stool), we are going to discover the different shades in which it can occur:

• Green breast milk: The mother’s diet influences breast milk. When milk turns greenish it may be because many green leafy vegetables or algae, isotonic drinks with colorings, or even an excess of vitamins have been consumed.
• black breast milk: The cause of milk having black pigments is certain drugs, as revealed by a scientific study. “This is a quite extraordinary case,” clarifies Inma Mellado. Also, according to the Australian Breastfeeding Association (ABA), if the milk is brown/chocolate, black or olive green it may mean the presence of blood.
• Orange breast milk: As with green, orange foods or drinks such as juices, carrots, pumpkin, jellies… can cause breast milk to turn slightly this color or acquire a yellowish tone.
• Red or pink breast milk: These discolorations may be due to a significant consumption of some foods such as beets, or to colorings in other food products, but they can also indicate other problems that should not be neglected. “On occasions when there is a crack in the breast, the milk may have a pink or reddish color due to the mixture with blood,” explains Purificación Barroso. In these cases, there is no problem because the baby takes it, but it is advisable to consult with the midwife or medical professionals specialized in breastfeeding to find solutions and prevent the problem from worsening. In addition, milk can acquire a bright pink color “due to an infection whose causative agent is the serratia marcescens bacteria,” says expert Mellado.

Brown breast milk from rusty pipes syndrome

During the first days of breastfeeding, the milk may have a dark brown or reddish color, similar to rust. This is due to what is called ‘rusty pipe syndrome’ or ‘rusty pipe syndrome’, which has a low incidence and is more common in first-time mothers. “This tone tells us that there are certain traces of blood. It is a benign syndrome, it usually occurs in the first days postpartum and is due to blood coming from certain small blood vessels in the glandular tissue,” explains the president of the Spanish Association of IBCLCs Inma Mellado.

It is, therefore, a physiological phenomenon in both breasts that is not painful, does not harm either the mother or the baby and, therefore, does not prevent breastfeeding, nor should it be interrupted, since it usually resolves in a few days. (approximately one week) without the need for any treatment and improves as milk production increases.

In this case we are not talking about any pathology, but it is always advisable to be aware of the secretions and consult the medical professional if, as advisor Barroso warns: “Any fluid comes out of our chest outside of the breastfeeding or pregnancy period, or if the fluid has a much clearer, sticky appearance, with traces of blood…”, as well as “if the secretion occurs spontaneously and, especially, if it does so only from one of the two nipples,” adds Inma Mellado. You have to be careful because, for example, some forms of breast cancer can cause bleeding.

Color changes in breast milk when expressing or storing it

The color of breast milk also changes a little when we express and store it. When we take it out, it presents a bluish-white color, almost gray; and when stored in the refrigerator, when it cools, it tends to separate into layers: at the top there is a thicker and creamier yellow or white one, and at the bottom a thinner, transparent or bluish one.

In addition, when frozen “it can acquire a somewhat more yellowish color. And if you store it in freezer bags, white spots may appear, especially visible if you store it horizontally, which do not pose any problem in the milk,” explains IBCLC Inma Mellado.

They are absolutely normal color changes, but what may worry us is that when it is defrosted it has a “sour smell and taste, like soapy or metallic. That is not because it has gone bad, but because lipase has been activated, which is an enzyme found in breast milk. This milk is perfectly consumable by our baby,” concludes lactation consultant Barroso.