Many benefits of breast milk to infant health are related to its bacteria and human milk oligosaccharides (HMO). As a prebiotic, human milk oligosaccharides contribute to the establishment of beneficial intestinal flora. Surprisingly, however, we know little about what happens when the microorganisms in the mother's breast milk reach the baby's intestine.
Therefore, in order to find out this, a group of scientists studied 107 healthy mothers and babies for five years. They detected the microbial content in women's breasts, skin around nipples and milk, and analyzed the baby's feces to determine which microorganisms constitute the baby's intestinal flora. They found that the bacteria in the baby's feces were similar to those of their mother, but not similar to those of other women who participated in the study, which indicated that the bacteria deposited in the baby's intestines were passed from mother to child through breastfeeding. This study, published in the Journal of Pediatrics of the American Medical Association, is the largest study to date, and found the transfer of microorganisms in breast milk to the baby's intestine.
"We can prove that there are bacteria in breast milk, which can be traced back to the bacteria in baby feces," said Dr. Grace Alder Rovandi, director of infectious diseases department at Mattel Children's Hospital, University of California. Aldrovandi added: "This supports the hypothesis that microorganisms are a mechanism by which breastfeeding provides benefits."
The mother's bacteria began to colonize the baby's intestines at birth and continued until breastfeeding. These inherited microorganisms play a key role in the health of infants, because they participate in training the immature immune system to identify beneficial bacteria and pathogens. "Breast milk is a good liquid. After millions of years of development, it has evolved to make babies healthy, especially their immune systems. " Aldrovandi said in a press release. During the five-year study, they were also able to calculate the relative abundance of each bacterium. Therefore, they observed that in the first month of life, the daily intake of breast-fed babies reached more than 75%, and nearly 30% of the bacteria in their intestines came from breast milk, while the bacteria in areola skin were about 65,438+00%. Researchers are not sure where the remaining 60% comes from. The researchers also confirmed that the more breast-feeding, the more similar the intestinal flora of the baby is to the flora in the mother's breast milk. The study also found that infants who continue to breastfeed after starting to eat solid food will have more beneficial bacteria in their intestines.
Alexander Khoruts, a gastroenterologist at the University of Minnesota, told Reuters: "We always thought that most of these microorganisms came from mothers." "They found that breastfeeding is the main source of microbial transfer in the first few months of life. I think this study provides supporting evidence for the current proposal, that is, exclusive breastfeeding for the first six months and continuing breastfeeding until 12 months. "
However, this study still does not solve the problem of how infants who only eat formula milk get beneficial bacteria in the intestine.
refer to
Relationship between bacterial community in breast milk and the establishment and development of intestinal flora in infants. JAMA Pediatrics, 20 17.