In August 2018, a post from “Parents R Us” about topical use of breastmilk to treat various conditions (archived here) appeared and has made the rounds online since, showing claims that have long been around in other forms as advice shared between parents:
Underneath a photograph of a ziplock bag full of breastmilk in syringes, a post claimed:
here are some facts for you
Did you know that 1 drop of breastmilk has 1 million white blood cells?
Original post by: Chelsea Leigh Ward
You can use breastmilk topically to treat the following:
Some eye infections (Please note, never in the eye, but put it our around the eye)
The list goes on and on, it’s literally liquid gold! Here’s my little life hack for when you need just a little bit of milk and don’t want to thaw out an entire bag!
**please consult your doctor to see if this is an option for you or your baby**
After stating that “one drop” of breastmilk contains a million white blood cells, the post lists off a number of minor topical ailments for which the substance is supposedly an effective treatment. A slightly more specific but unsourced claim that one milliliter of breastmilk contains between one and five million “white blood cells” appears on two blogs, but is otherwise unsourced. Both Medela (a breastfeeding supply company) and a 2018 paper note that there are “millions” of cells in breast milk (not in just one drop), and that some are white blood cells.
One study determined that the composition of breastmilk changes over time, concluding that it varies and depends on various intertwined issues, such as “stage of lactation, the degree of breast fullness, infant feeding, the mother and infant health status, and many other factors and may be associated with the maternal diet and environment, and potentially with genetic factors.” It cited concentrations well below the “one to five million per drop” estimate, though, with respect to a type of cell known as a leukocyte:
The stage of lactation is associated with major changes in milk leukocyte composition . Using multicolor flow cytometry to identify and quantify leukocyte subsets in breast milk obtained from healthy women, Trend et al. found that colostrum contains approximately 146,000 cells/ml and that the amount decreases in transitional (8–12 day postpartum) and mature milk (26–30 day postpartum) to 27,500 and 23,650 cells/ml, respectively . They also demonstrated that breast milk contains a greater variety and complexity of leukocyte subsets than previously thought.
Similar ranges were cited in a separate study. Colostrum, which is only expressed for a brief period after birth, was found to have far higher concentrations of such cells than transitional milk. A similar study in 2018 noted that ingested white cells did survive infants’ gastric systems and remained active for up to six days.
The broader post was about the use of breastmilk as a topical treatment. A 2018 Parents.com article about topical uses for breastmilk opens by claiming that the antibacterial properties of breastmilk have been proven, but it links to a study about ingested breastmilk rather than topical applications. When infection was mentioned in that research, it referred to breastfed infants and consumption of breastmilk.
Parents.com’s list of six topical uses for breastmilk cites a midwife and lactation consultant as its source, and both professions are known to recommend the use of breastmilk for ailments like maternal mastitis or cradle cap in infants. Of the six conditions mentioned in the article, only one (diaper rash) involved links to research. The site linked to a summary of a small study in 2015 finding breastmilk to be as efficient as hydrocortizone in treatment of diaper rash, and similar research supporting the same conclusion in 2013.
The 2015 research found breastmilk to perform slightly better than ointment, and it cited earlier research on topical use of breastmilk for umbilical cord separation sites [PDF] as well as maternal mastitis:
The frequency of healed infants was 81.5% and 76% in HBM and 1% hydrocortisone groups on day 21 respectively … Pishva et al. indicated the topical application of HBM as having beneficial effects on the prevention of neonatal conjunctivitis. Mohammadzadeh et al. showed the therapeutic effect of HBM and lanolin on sore nipples. HBM was found to heal nipples faster than using lanolin.
Ahmadpour and his colleagues compared the effects of topical HBM to ethyl alcohol 96%, dry care, and silver sulfadiazine groups on the umbilical cord separation time. They showed that the mean cord separation time in the HBM group was significantly shorter than the other groups.
A broader meta-study on the topical uses of breastmilk was published in May 2019. In its concluding paragraphs, researchers noted “considerable heterogeneity” in the studies, meaning that their parameters were diverse enough to make it difficult to draw conclusions. They added that the most reliable clinical studies for assessing the benefits of breastmilk are “randomized, double-blinded, multicenter controlled trials but to date, they are very scarce.”
Its authors also listed the pros for topical application of breastmilk (cost, convenience, and low risk of side effects) with the cons (poorly demonstrated efficacy as a whole) and a significant number of variables (conflicting outcomes and inconsistencies in breastmilk overall):
Common skin problems may appear during lactation and breastfeeding, particularly affecting the nipple, areola, and breast. Some medications used in the treatment of skin conditions are unsuitable during lactation. It has been shown that expressing a few drops of milk and rubbing them gently into the sore nipples, then allowing it to dry naturally, takes advantage of the healing properties of human milk. Many studies have indicated that bioactive components of human milk and microbiota have promise as adjuvants for wound healing. From lesions of the corneal epithelium to lacerations of the skin, milk-treated groups healed faster than controls.
Breast milk is used in many cultures for skin irritations. Breast milk involves no risk of allergy, contains antibodies, epidermal growth factor (EGF), and erythropoietin, which may promote the growth and repair of skin cells. Human milk is a source of commensal bacteria that can play an anti-infectious, immunomodulatory role. Their possible function in the acceleration of conditions for skin biofilm formation can open new perspectives for the prevention and treatment of skin and wound healing diseases. Interestingly, the analysis of Simpson et al. showed that miRNAs are possible mediators of the observed preventative effects of atopic dermatitis.
The concentration, regulation, and individual variation between bioactive element, immune factors, various progenitor and mature cell types, and stage of lactation are not well established. Complexity and variability in human milk composition, and infants’ responses to many human milk constituents may also explain some of the conflicting results of studies evaluating the effects of non-nutritional uses of human milk.
The studies considered here vary in methodology and in definition of outcomes, which leads to considerable heterogeneity. Human milk composition varies both within and between individuals, and this may partially explain the conflicting data.
The Facebook post touting the efficacy of breastmilk as a topical treatment racked up several tens of thousands of shares, a testament to its popularity as folk medicine. In recent years, numerous studies have attempted to determine whether those claims were provable, with limited success. Variations in breastmilk and study outcomes have not yet shown breastmilk to be a substitute for more conventional topical treatments, although it has demonstrated some use in applications for skin conditions like diaper rash. Consulting a doctor before eschewing standard treatment is advisable — although breastmilk in and of itself is not likely to pose much risk to the nursing infant or their mother.