Written by James McIntosh
Researchers testing the origins of human breast milk samples available for purchase online found that around 10% of the samples they examined contained significant amounts of added cow's milk.
The pressure on parents to feed newborn infants with breast milk may be leading many to purchase human breast milk online. However, the milk they receive from online vendors may not match up to what is being offered.
"They purchase the milk online based on a posted description of the type and quantity of the milk or the health habits of the seller," writes study author Dr. Sarah Keim. "But when they think they're getting nutritious, high-quality breast milk, some of them are actually receiving human milk mixed with cow's milk."
Human breast milk is widely recognized as providing many health benefits to young infants. According to the American Academy of Pediatrics (AAP), breastfeeding can protect against diseases and conditions such as diarrhea, diabetes and childhood obesity.
However, many new mothers find themselves unable to breastfeed. In 2012, a survey published in Pediatrics found that two-thirds of mothers nursing newborns are unable to manage breastfeeding for as long as they intended.
"Some women are unable to produce enough milk for their infant or perceive they cannot meet their infant's needs, yet they may be reluctant to feed formula," write the researchers of the new study. For these mothers, the Internet represents an alternative way of providing human milk for their children.
'You do not truly know what you are receiving'
For the study, published in Pediatrics, Dr. Keim and her colleagues purchased 102 samples of what was advertised as human milk from sellers on the Internet. These milk samples were subjected to DNA testing in order to verify their human origins and to assess whether any cow's milk was also present.
While all of the purchased Internet samples contained human DNA, 11 also contained bovine DNA. Of these, 10 contained bovine DNA concentrations significant enough to suggest that cow's milk had been added to human milk, being so high that accidental contamination was unlikely.
The inclusion of cow's milk in human breast milk can be problematic for babies. It can potentially be harmful due to cow's milk allergies, health conditions or formula sensitivities. The inclusion of cow's milk could also reduce a baby's access to the essential nutrients and fats that are in formulas and human breast milk but not cow milk.
"The truth of the matter is that you do not truly know what you are receiving when you buy milk from a stranger over the Internet," explains Dr. Keim.
"Selling breast milk gives people an incentive to add cow's milk or formula to the milk in order to sell more. When money is involved in an unregulated process like this, you cannot know for sure that the milk is safe to give to your baby."
Although the sample used in the study is acknowledged as small by the authors, they state the sample is representative of Internet sellers and has given the researchers findings that may at least generalize to milk being sold via the Internet.
"Our findings confirm the previously theoretical risk that human milk being sold via the Internet may not be 100% human milk," the authors conclude. "Because buyers have little means to verify the composition of the milk they receive, all should be aware of the possibility that it may be adulterated."
Previously, in a report published in The BMJ, experts claimed that breast milk purchased online can pose serious health risks to infants, largely due to a lack of regulation. Human milk is not tested for contamination or disease and could be stored incorrectly.