No Evidence for Sex‐specificity in Vitamins C, E, and Fatty Acid Content of Human Milk from Healthy Polish Mothers

Abstract

Objectives: Human milk (HM) is a complex fluid that meets the nutritional needs of infants. Its composition is associated with environmental, maternal, and fetal variables. It provides nutrients and bioactive substances, including cytokines, immunoglobulins, and constituents with antioxidative properties. Boys are reportedly more susceptible to oxidative stress. This study aimed to determine the relationship between infant sex and the antioxidants vitamins C and E, and the fatty acid (FA) profile of HM. Results of this investigation may infer sex differences for the composition of infant formulas. Methods: Thirty days after delivery, a sample of HM was collected from 152 healthy, non-smoking mothers of full-term new-borns (77 males) born in good clinical condition. After FAs were extracted from the fat component, they were converted into methyl esters and separated using highperformance gas chromatography. Tocopherol content was determined using a method described in a previous study. Vitamin C content was determined using reversed-phase high-performance liquid chromatography with ultraviolet detection, as described in the same study. Results: The study groups (male vs female offspring) did not differ in terms of vitamin and FA content in HM. The only difference found was in gondoic acid 20:1 (n-9), with a higher concentration in the HM of mothers with female offspring (mean 0.63 AE 0.18 vs 0.59 AE 0.15 g/100 g FA; P < 0.047). Conclusions: Despite the acknowledged differences in the composition of HM associated with infant sex and the increased oxidative stress in males, antioxidant content did not appear to differ according to infant sex. These results suggest that there is no need for the antioxidant content of infant formulas to be sex-specific.

Potential sex differences in human milk fatty acids and their association with atopic dermatitis: Results of the Ulm SPATZ health study

“…Furthermore, some of these previous studies 17,32,33 which showed no sex‐specific differences in PUFAs only included data on human milk samples collected up to 4 months post‐partum. However, we have previously shown that fatty acid composition changes during the first 12 months of lactation 24 .…”

“…As such, these potential sex differences might depend on the time interval for sample collection. Moreover, the aforementioned research 17,32,33 has neglected the compositional aspect of fatty acids. As a result, there is a limited availability of compositional analyses in this regard 16 .…”

“…Furthermore, some of these previous studies 17,32,33 which showed no sex-specific differences in PUFAs only included data TA B L E 2 Relative proportions (%) of polyunsaturated fatty acids in human milk samples for all children and stratified by infant sex at 6 weeks postpartum. on human milk samples collected up to 4 months post-partum.…”