Human milk oligosaccharides in Chinese lactating mothers and relationship with allergy development in offspring

Background: The health benefits of breastfeeding are partly contributed by human milk oligosaccharides (HMOs), but there is limited data on breast milk (BM) HMO composition in Chinese.

Objective: This study investigated the association between early-life HMO intake and allergy occurrence in Chinese children.

Methods: 103 healthy Chinese pregnant women regardless of allergy history were recruited into this birth cohort. Their babies were followed until 24 months old. Concentrations of 2'-fucosyllactose (2'-FL), lacto-N-neotetraose (LNnT), -sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL) in BM collected at 1-month postpartum were measured by liquid chromatography-mass spectrometry. The associations between these HMOs and allergy occurrence by 24 months were analyzed by multivariate regression analyses.

Results: Twenty-nine percent and 19% of participants had eczema at 12 and 24 months old respectively. Eighty BM samples were analyzed, with 2'-FL being the most abundant HMO (median 1447 ppm, interquartile range [IQR] 291-1906 ppm), and median (IQR) levels of LNnT, 6'-SL and 3'-SL in ppm were 738 (580-950), 20.5 (12.7-38.8) and 23.0 (17.8-27.6) respectively. Participants with eczema by 24 months consumed BM with higher 2'-FL concentration at 1-month (P = 0.008), and also lower 6'-SL concentration in exclusively breastfed infants (P = 0.012) but higher 6'-SL concentration for those with mixed feeding at 1 month (P = 0.043). Food allergic children at 12 months consumed BM with higher 2'-FL concentrations at 1 month (P = 0.048).

Conclusions: BM 2'-FL concentration is higher in children who develops eczema by 24 months and food allergy during infancy. The relationship for 6'-SL is divergent depending on mode of feeding in infants.