Impact of Environmental Exposures on Human Breast Milk Lipidome in Future Immune-Mediated Diseases

The composition of human breast milk (HBM) exhibits significant variability both between individuals and within the same individual. While environmental factors are believed to play a role in this variation, their influence on breast milk composition remains inadequately understood. Herein, we investigate the impact of environmental factors on HBM lipid composition in a general population cohort. The study included mothers (All Babies In Southeast Sweden study) whose children later progressed to one or more immune-mediated diseases later in life: type 1 diabetes (n = 9), celiac disease (n = 24), juvenile idiopathic arthritis (n = 9), inflammatory bowel disease (n = 7), hypothyroidism (n = 6), and matched controls (n = 173). Lipidome of HBM was characterized by liquid chromatography combined with high-resolution mass spectrometry. We observed that maternal age, body mass index, diet, and exposure to perfluorinated alkyl substances (PFASs) had a marked impact on breast milk lipidome, with larger changes observed in the milk of those mothers whose children later developed autoimmune diseases. We also observed differences in breast milk lipid composition in those mothers whose offspring later developed autoimmune diseases. Our study suggests that breast milk lipid composition is modified by a complex interaction between genetic and environmental factors, and, importantly, this impact was significantly more pronounced in those mothers whose offspring later developed autoimmune/inflammatory diseases. Our findings also suggest that merely assessing PFAS concentration may not capture the full extent of the impact of chemical exposures; thus, the more comprehensive exposome approach is essential for accurately assessing the impact of PFAS exposure on HBM and, consequently, on the health outcomes of the offspring.
This study was supported by the Swedish Research Council (grant nos. and 2020-03674 and 2016-05176 to T.H. and M.O.), Formas (grant no. 2019-00869 to T.H. and M.O.), and the Novo Nordisk Foundation (grant nos. NNF20OC0063971 and NNF21OC0070309 to T.H. and M.O.). ABIS study (J.L.) was supported by Barndiabetesfonden (Swedish Child Diabetes Foundation); the Swedish Council for Working Life and Social Research, grant/award numbers: FAS2004-1775 and FAS2004-1775; the Swedish Research Council, grant/award numbers: K2005-72X-11242-11A, K2008-69X-20826-01-4, and K2008-69X-20826-01-4; Östgöta Brandstodsbolag; the Medical Research Council of Southeast Sweden (FORSS); the Wallenberg Foundation, grant/award number: K 98-99D-12813-01A; ALF-and LFoU grants from Region Östergötland and Linköping university, Sweden; and Joanna Cocozza Foundation.