Relationship between the intake of fibre-rich foods and the presence of butyric acid in breast milk of Chilean mothers

Abstract

Introduction: The maternal gut microbiota ferments dietary fibre (DF), generating short-chain fatty acids (SCFAs) that can be transferred to breast milk (BM). Butyric acid, which has been identified in BM, stands out for its nutritional relevance and anti-inflammatory effects on the infant’s digestive metabolism.

Objective: To evaluate the relationship between maternal DF intake and the presence of butyric acid in the BM of Chilean mothers.

Materials and Methods: A cross-sectional, correlational study was conducted with 20 mothers who were exclusively breastfeeding infants aged between 26 and 64 days. The infants were born at term, had an adequate birth weight and length, and were otherwise healthy. Sociodemographic, dietary, and health data were collected, along with 10 ml BM samples. Lipid content was determined using the Roese-Gottlieb method, and SCFAs were analysed by gas–liquid chromatography. Data were analysed according to their distribution using SPSS 23.0 and Food Processor 2.0. The study was approved by the Ethics Committee of the University of Chile.

Results: Participants were 30.65 ± 4.8 years old and had 2 ± 1 children; 68.4% were obese, 5.3% overweight, and 26.3% of normal weight postpartum. Energy intake averaged 1956 ± 645 kcal/day, and total DF intake was 23 ± 8.4 g/day (insoluble 3 ± 1 g/day; soluble 7 ± 2.8 g/day), mainly provided by cereals (52.4%), vegetables (21.8%), and fruits (10.7%). Butyric acid concentration in BM was 7.05 ± 8.92 mg/dL. A positive correlation was observed between total DF intake (r=0.7428; p=0.002) and insoluble DF (r=0.7410; p=0.0001) with butyric acid content in BM.

Conclusion: A higher intake of total and insoluble dietary fibre (DF) by mothers is associated with increased levels of butyric acid in breast milk (BM), highlighting the importance of promoting its consumption during the postpartum period to improve BM composition and potentially benefit infant health.