Study Looks at How Changes in Maternal Diet Impact Human Milk Oligosaccharides and the Milk Microbiome Essay
LAS VEGAS (Jan. 23, 2017)—In a study to be presented Thursday, Jan. 26, in the oral plenary session at 1:15 p.m. PST, at the Society for Maternal-Fetal Medicine’s annual meeting, The Pregnancy Meeting™, researchers with Baylor College of Medicine, Houston, Texas and University of California, San Diego, La Jolla, California, will present their findings on a study titled, Maternal Diet Structures the Breast Milk Microbiome in Association with Human Milk Oligosaccharides and Gut-Associated Bacteria.
Previous studies have shown that a high fat maternal diet during gestation and lactation has a long-term impact on the infant’s gut microbiome (the community of bacteria living inside the human gut.) This study represents the first step in understanding whether breast milk contributes to this process.
In this study, researchers found that specific changes to maternal diet in the same woman (changing fat versus carbohydrate consumption, or changing consumption of specific sugars), is associated with changes in both the milk microbiome and human milk oligosaccharide (a carbohydrate) composition. Given that these two components of breast milk have the potential to alter the gut microbiome of breast-feeding infants, the results of the study suggest that development of the infant gut microbiome may be affected in part by what the mother eats during breastfeeding.
“Further studies are needed to delineate if specific changes in maternal diet during breast-feeding alter the infant gut microbiome and to determine if this results in any health consequences for the infant,” said Kristen Meyer, in the Department of Obstetrics and Gynecology at Baylor College of Medicine and the presenter of the study at the SMFM annual conference. “Ultimately, we would hope that future studies would form dietary guidelines for breastfeeding mothers to promote healthy development of their infants’ gut microbiota,” Meyer added.
Abstract #20 Maternal diet structures the breast milk microbiome in association with human milk oligosaccharides and gut-associated bacteria
Kristen M. Meyer¹, Mahmoud Mohammad¹ , Lars Bode² , Derrick M. Chu¹ , Jun Ma¹ , Morey Haymond¹ , Kjersti Aagaard¹ ¹Baylor College of Medicine, Houston, TX, ²University of California, San Diego, La Jolla, CA
OBJECTIVE: We have previously shown that a high fat maternal diet (HFD) during gestation and lactation has a long-term impact on the offspring gut microbiome. However, the relative contribution of breast milk is unknown. In this study, we sought to determine mechanisms by which diet may modulate composition of the milk microbiota. Specifically, given the role of human milk oligosaccharides (HMOs) in protection against both dysbiosis and necrotizing enterocolitis, we hypothesized that there may be an interaction between maternal HFD, HMOs, and the breast milk microbiome.
STUDY DESIGN: Two dietary treatments were tested in single-blinded cross-over dietary intervention studies of lactating women. The first cohort (n = 7) received a high fat or carbohydrate diet, with a 1-2 week washout period. The second cohort (n = 7) received 60% of their daily caloric intake from either glucose or galactose, with a 1 week washout period. Milk samples collected after each dietary treatment were subjected to 16S metagenomic analysis and HPLC/ MS to profile the microbiome and HMO composition, respectively.
RESULTS: High fat versus carbohydrate diet significantly alters the milk microbiome (p = 0.038, Figure A), including significant shifts in several gut-associated taxa (Figure B). High fat diet decreases concentration of sialylated HMOs (p = 0.02, Figure C), and glucose versus galactose diet significantly alters concentration of fucosylated HMOs (p ¼ 0.02, Figure C). Intriguingly, sialylated HMO concentration is significantly correlated with microbiome composition in both dietary cohorts (p = 0.0015, Figure D), suggesting these HMOs play a key role in structuring the milk microbiome.
CONCLUSION: Maternal diet significantly alters the milk microbiome, HMO composition, and abundance of gut-associated taxa. These findings suggest that dietary influence on the milk microbiome is mediated in association with an altered proliferation of bacteria due to changes in sialylated HMO concentration. Additionally, we speculate that shifts in the maternal gut microbiome are translated to the milk microbiome via trafficking of enteric bacteria, resulting in the observed shifts in gut-associated taxa in breast milk.