Am J Hum Biol. 2025 Feb;37(2):e70006. doi: 10.1002/ajhb.70006.
ABSTRACT
INTRODUCTION: Social factors, such as kin and non-kin support in helping the mother of a newborn baby, impact the duration of lactation and may affect human milk composition. Recent studies suggest that maternal stress negatively affects the level of polyunsaturated fatty acids in human milk, which are crucial for infant vision and brain development. We suggest that social support may have the potential to attenuate a negative effect of stress on the composition of human milk fatty acids.
METHODS: We studied 129 exclusively breastfeeding mothers and their healthy, term infants to explore the relationship between support from significant others (structural and functional) and the concentration of docosahexaenoic acid (DHA, N = 49) and arachidonic acid (AA, N = 129) in human milk. We also examined whether maternal stress reactivity (log Cort. AUC) may be related to these fatty acids. Gas chromatography was used to analyze the concentration of DHA and AA in human milk samples.
RESULTS: Analyses revealed a positive association between the number of helpers (structural support) and the concentration of DHA and AA. Maternal stress reactivity was not a statistically significant predictor of DHA and AA contents in milk and was unrelated to the number of helpers.
CONCLUSION: Our results show for the first time that human milk composition, particularly DHA and AA concentrations, may be associated with the size of mothers’ immediate social network of kin and non-kin helpers. This result is consistent with evolutionary studies that emphasize the role of cooperative breeding in human reproduction.
PMID:39915968 | DOI:10.1002/ajhb.70006
