Without a doubt, breast milk is the best for a baby’s health, especially during the first two years of life. A recent study, published in the online journal Current Nutrition & Food Science, also reveals that breast milk boosts the growth of friendly bacteria in the gut, which play an important role in proper nutrient absorption and immune system development in babies.
According to the study’s senior author, associate professor of surgery William Parker from Duke University Medical Center in Durham, North Carolina, theirs is the first study that looked at how infant nutrition, particularly breast feeding, affects bacterial growth as compared to using infant formula.
Numerous studies have already established the many health benefits of breast feeding. Breast milk helps protect babies from diarrhea, respiratory infections, the flu, and other common health conditions; it also reduces the likelihood that they will develop allergies, type 1 diabetes, and other diseases later in life. All these early findings indicate an association with the type of diet a baby has and how it affects the growth of healthy intestinal flora.
Parker added, “Only breast milk appears to promote a healthy colonization of beneficial biofilms, and these insights suggest there may be potential approaches for developing substitutes that more closely mimic those benefits in cases where breast milk cannot be provided.”
Parker and his colleagues used cow’s milk in the form of whole milk available in grocery stores; three popular brands of infant formula; and breast milk given by volunteers. Additionally, they isolated the antibody secretory immunoglobulin A (SIgA) from the breast milk and used this as a separate culture medium. Human breast milk is rich in this antibody and is largely responsible for immune system development in babies. They grew cultures of two strains of E. coli in each of these samples; these strains are critical to the growth of intestinal flora and closely related to the other strain of E. coli that cause food poisoning.
The bacteria grew in all four culture mediums but there were differences in the development of the colonies in the different samples.
The bacteria grown in human breast milk were clumped together and formed biofilms, the layer which protects the bacteria from pathogens. The bacteria grew prolifically in the cow’s milk and infant formulas but they did so as separate organisms, not aggregated within a biofilm like the bacteria in the breast milk. The bacteria grown in the SIgA sample exhibited a mixture of both individual bacterium and aggregated bacteria; this suggests that SIgA alone is not enough to promote the growth of beneficial gut bacteria.
The findings suggest that human breast milk facilitates bacterial growth and aggregation by using “multiple mechanisms,” whereas cow’s milk and infant formula only promote the growth of plankton-like bacterial colonies. Parker said their study could help in the development of infant formula that would also provide the same benefits as human breast milk so that infants who are not able to drink breast milk may still receive the associated health benefits.