By Caitlin St John
April 06, 2015
Milk in bottle

There is no disputing that the benefits of feeding an infant breast milk are huge, but not all mothers are able to produce enough milk to feed their newborns. This has caused many mothers (approximately 55,000!) to turn to the internet to purchase milk from other nursing moms.

However, new research conducted by Nationwide Children's Hospital has proved that this is a potentially harmful decision.

Researchers found that what was being advertised as pure human milk wasn't at all. "We found that one in every 10 samples of breast milk purchased over the Internet had significant amounts of cow's milk added," said Sarah A. Keim, Ph.D., lead author of the study and principal investigator in the Center for Biobehavioral Health in The Research Institute at Nationwide Children's. This is especially dangerous for infants under 12 months who lack the ability to digest cow's milk properly, and for breastfeeding kids who may have a milk allergy or dairy intolerance.

"We don't know for sure why cow's milk was in the milk that we purchased, but because this milk was sold by the ounce sellers may have had an incentive to add cow's milk or formula to boost the volume," Keim told It's likely that some sellers are profit-driven as breast milk is typically sold for $1-$2 per ounce.

And this is not the first time mothers have been warned against purchasing breast milk over the internet. In 2013, Keim and her team found that 75 percent of breast milk samples that had been bought online contained high levels of bacteria that could make an infant ill.

The only way to avoid contaminated, and possibly dangerous, breast milk, is to not purchase it at all. Mothers who are having trouble breastfeeding or pumping should seek the advice of a medical professional. "They should work closely with their pediatrician to come up with a plan for feeding their baby that meets their unique needs, in terms of how well they are growing, and if there are any medical conditions or allergies," said Dr. Keim. "For mothers who want to breastfeed, early and high quality lactation support can be very helpful for many women in addressing problems that come up."

Caitlin St John is an Editorial Assistant for who splits her time between New York City and her hometown on Long Island. She's a self-proclaimed foodie who loves dancing and anything to do with her baby nephew. Follow her on Twitter: @CAITYstjohn

Image: Bottle with milk via Shutterstock