Children who consume breast milk for six months have a lower risk for childhood leukemia than those who don't, according to a new study reported on by Time magazine.
In their investigation published in JAMA Pediatrics, Efrat Amitay, PhD of the University of Haifa's School of Public Health in Israel, and a colleague analyzed 18 studies on the topic of breastfeeding and childhood leukemia, the most common type of childhood cancer.
"We still don't know what causes childhood leukemia," Amitay said. "There have been all kinds of hypotheses about it, and one of the things that emerged in the research is breastfeeding."
They found that breastfeeding a child for six months or longer was associated with a 19 percent lower risk for childhood leukemia, compared to children who had been breastfed for less time or not at all.
Though breast milk is widely accessible for infants, little is actually known about the science behind why the liquid is so powerful.
"There's still a lot to learn about the biology of it," said Amitay. But evidence continues to mount that breast milk is a live substance full of immune-promoting and anti-inflammatory compounds, and that it helps develop the immune system and a healthy microbiome. Baby formula, on the other hand, also seems to change gut microbes, but not for the better, as research shows that breast-fed babies have more natural-killer cells—a type of immune cell that targets and destroys cancer cells—than children fed with formula, the study reports.
Then there are animal studies which found that breast milk contains stem cells that may be similar to embryonic stem cells, meaning they can change inside an infant's body and perform where they're needed, said Amitay.
"When you talk about breast milk, it's more accessible and less controversial than embryonic stem cells," she said. "It's still all very, very at the beginning, but I think it's very exciting, too."