Associations of Region and Lactation Stage with Odd-Chain Fatty Acid Profile in Triglycerides of Breast Milk in China

Abstract

Odd-chain fatty acids (OCFAs), with potential value for growing infants, have been reported in breast milk. The association of location and lactation stage with the profile and content of OCFAs in breast milk was studied. We analyzed 1487 breast milk samples collected from 12 areas in China, and 102 infant formulas from different brands were purchased from the local supermarket. The content of sn-2 C15:0 significantly decreased from the colostrum to the mature stage, while that of C17:0 was not significantly increased by the lactation stage (p > 0.05). The content of C15:0 and C17:0 significantly decreased dramatically after the colostrum period, while the content of C13:0 was highest in the mature stage. The level of C15:0 and C17:0 in human milk from Gansu and Xinjiang was significantly higher than that from other areas. Similar trends were observed on the level of sn-2 C15:0 and C17:0, whereas the content of sn-2 C11:0 and C13:0 was significantly higher in breast milk from Shandong. Based on the PDS-LA analysis, the difference among infant formulas, each stage of human milk and human milk from different locations were different. Research is needed to determine if there are health benefits associated with OCFAs.

Concentration and composition of odd-chain fatty acids in phospholipids and triacylglycerols in Chinese human milk throughout lactation

“…C17:0 is the most abundant in both PL-OCFA and TAG-OCFA, much higher than the second most abundant C15:0, in line with a previous study. 28 A similar trend is observed in serum (C15:0 of 0.22%, C17:0 of 0.37%), 34 where C17:0 dominates as the most abundant OCFA followed by C15:0. Interestingly, OCFAs are primarily obtained from dairy products, 13 where the ratio of C15:0 to C17:0 is approximately 2 : 1.…”

“…In human milk, OCFAs are predominated by C17:0 (0.29%), followed by C15:0 (0.19%). 28 Conversely, OCFAs in cow's milk mainly consist of C15:0 (0.84%) rather than C17:0 (0.40%), [41][42][43] while the level of C15:0 and C17:0 in infant formula are even below 0.05%. 28 Given the complex structure and function of OCFAs, future research should focus on examining both the content and composition of OCFAs in PLs and TAGs.…”

“…28 Conversely, OCFAs in cow's milk mainly consist of C15:0 (0.84%) rather than C17:0 (0.40%), [41][42][43] while the level of C15:0 and C17:0 in infant formula are even below 0.05%. 28 Given the complex structure and function of OCFAs, future research should focus on examining both the content and composition of OCFAs in PLs and TAGs. This could provide scientific evidence for better development of secure and effective human milk surrogates for infants without access to breast milk.…”

“…28 This study specifically investigated the levels of C11:0, C13:0, C15:0 and C17:0 and established association between TAG-OCFAs and different lactation stages. 28 It is important to note that few studies have been conducted on PL-OCFAs, despite their potential health benefits reported previously. [18][19][20][21] While research on human milk OCFAs is still in its early stages, further exploration of their profiles in human milk is warranted.…”

“…28 This study specifically investigated the levels of C11:0, C13:0, C15:0 and C17:0 and established association between TAG-OCFAs and different lactation stages. 28 It is important to note that few studies have been conducted on PL-OCFAs, despite their potential health benefits reported previously. 18–21…”