Breastfeeding during early infancy leads to significant gut microbiota differences at 3 to 4 months compared with formula feeding or supplementation, and these differences may protect breastfed infants against risk for overweight at 12 months, according to a study published in JAMA Pediatrics.
The study analyzed data on 1087 infants (507 girls and 580 boys) enrolled in the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort. At 3 months, breastfeeding practices for these infants were classified as none (formula only), partial (formula and breast milk), or exclusive (breast milk only). At 6 months, practices were classified as not breastfed (formula only with or without complementary foods), partial without formula (breast milk with complementary foods), partial with formula (formula and breast milk with or without complementary foods), and exclusive (breast milk only).
Gut microbiota were assessed through fecal samples collected at approximately 3 months and 12 months. Analysis showed that earlier supplementation with formula and earlier cessation of breastfeeding were linked to a dose-dependent increase in the risk for overweight at 12 months. The feeding practices and gut microbiota differences found at 3 months had a stronger impact on risk for overweight than those identified at 12 months.
The study investigators conclude, “Formula feeding was associated with higher microbiota diversity and enrichment of Lachnospiraceae at 3 to 4 months, and these microbiota features partially explained the increased risk of overweight among nonbreastfed infants. Subtle but statistically significant differences in the microbiota were observed after brief exposure to formula in the hospital, although the clinical implications of these changes are unclear. Together, these results identify important areas for future research and emphasize the importance of early infancy as a critical period during which transient gut dysbiosis is associated with the subsequent risk of overweight.”
Forbes JD, Azad MB, Vehling L, et al; for the Canadian Healthy Infant Longitudinal Development (CHILD) Study Investigators. Association of exposure to formula in the hospital and subsequent infant feeding practices with gut microbiota and risk of overweight in the first year of life [published online June 4, 2018]. JAMA Pediatr. doi:10.1001/jamapediatrics.2018.1161