Carotenoids and Fatty Acids in Early Lactation: A Study of a Peruvian Population
Lipid soluble carotenoids are micronutrients present in human milk that serve as precursors of vitamin A and also play an important role protecting cells from damage arising from photooxidative processes and reactive oxygen species. Fatty acids comprise about 3-5% of human milk and are mainly present as triglycerides. They are a major energy source for the infant and are necessary to support cell growth required for normal development and maturation of critical organs. Transport of carotenoids into milk has been little studied and there has been no previous investigation of the relationship of carotenoid transport with that of individual fatty acid secretion into milk. ^ In the present study, levels of the carotenoids, lutein, zeaxanthin, β-cryptoxanthin, and β-carotene, in maternal serum, infant cord blood, and milk obtained from 74 Peruvian mothers were measured by HPLC methods. The fat content and fatty acid profile of maternal milk were determined by GC-FID and confirmed by GC-MS. Twenty nine fatty acids were identified and quantified after conversion to methyl esters. Statistical analysis was employed to investigate potential trends and relationships among the carotenoids in all three fluids as well as between carotenoids and fatty acids present. ^ Concentrations of lutein in maternal serum and milk as well as maternal serum and infant cord blood were highly correlated (r =0.43, p<0.03) and (r=0.40, p<0.05), respectively. Body mass index was inversely correlated with the concentration of provitamin A carotenoids in milk and serum. Carotenoid concentrations declined during the initial weeks of lactation and did not significantly correlate with fat content which remained constant. Concentrations of essential n-3 and n-6 fatty acids were found to be in the upper quartile among others populations studied worldwide. An inverse correlation between lutein and the concentrations of linoleic acid (r=-0.432, p<0.02) and á-linoleic acid (r=-0.435, p<0.02) present in transitional milk was seen. Moreover, secretion of carotenoids into milk shows a positive correlation with a small number of fatty acids that are metabolically produced within the mammary duct. A competitive relationship between the transport of these essential polyunsaturated fatty acids is hypothesized to play a role in the secretion of early milk but not that of mature milk.^
Mendez, Vanesa, "Carotenoids and Fatty Acids in Early Lactation: A Study of a Peruvian Population" (2016). ProQuest ETD Collection for FIU. AAI10743716.