Psychosocial stress and cortisol stress reactivity predict breast milk composition

Anna Ziomkiewicz,Anna Apanasewicz,Agnieszka Cierniak,Magdalena Babiszewska,Dariusz Danel,Marek Szołtysik,Szymon Wichary,Magdalena Piosek,Patrycja Wychowaniec,Olga Barbarska

doi:10.1038/s41598-021-90980-3

Abstract

We studied a sample of 146 Polish, exclusively breastfeeding mothers and their healthy born on time infants to explore the effect of perinatal psychosocial stress on breast milk composition. Maternal perinatal stress was assessed using Recent Life Changes Questionnaire summarizing stressful events from the previous six months. Stress reactivity was determined by administering the cold pressor test and measuring cortisol in saliva samples taken during the test. Breast milk sample was taken to measure energy, protein, fat, lactose, and fatty acid content. Analyses revealed that stress reactivity was positively associated with milk fat and long-chain unsaturated fatty acids and negatively associated with milk lactose. Perinatal psychosocial stress negatively affected energy density, fat as well as medium-chain and long-chain saturated fatty acids in milk. These results, together with previous studies, advocate monitoring maternal psychological status during the peripartum to promote breastfeeding and healthy infant nutrition.

Highlights

Stress on breastfeeding initiation, duration, and exclusivity, only a few studies examined the impact of stress on breast milk composition[12]
Chronic stress affects body composition by increasing fat a ccumulation[17]. This may result in a higher concentration of lipids and specific fatty acids in breast milk, because milk fat synthesis partly relies on maternal fat r esource[18]
No differences in maternal and infant characteristics were found between groups of mothers with low vs. high recent life changes (RLC) except for the total cortisol level ( CortAUC)during the cold-pressor test (CPT), which was higher in high RLC mothers (p = 0.05)

Summary

Introduction

Stress on breastfeeding initiation, duration, and exclusivity, only a few studies examined the impact of stress on breast milk composition[12]. Cortisol rising in response to short-term stressors in breastfeeding mothers may increase the level of substrate necessary for carbohydrate and lipid synthesis and, result in higher lactose and fat levels in milk. Indirect pathways may include effects on dietary intake in response to long-term stressors Studies evidence both the increase and the decrease in the consumption of energy-dense food during periods of high perceived stress[15,16,17]. Chronic stress affects body composition by increasing fat a ccumulation[17] This may result in a higher concentration of lipids and specific fatty acids in breast milk, because milk fat synthesis partly relies on maternal fat r esource[18]. Overall, the effect of psychological stress, which frequently accompanies childbirth and childcare, remains unclear

Methods

Results

Conclusion