Xanthophylls in Human Milk and Maternal Diet: A Cross-sectional Analysis of Data from the Japanese Human Milk Study Cohort

Maternal diet and sociodemographic factors influence xanthophyll concentration and composition in human milk. However, the importance of dietary patterns regarding the intake of fruits, vegetables, and xanthophylls remains unclear. The aim was to determine the composition of xanthophylls in the human milk of Japanese mothers and explore associations of xanthophylls with dietary and sociodemographic factors. This cross-sectional study was conducted in the early phase of the Japanese Human Milk Study. Xanthophyll content was measured using liquid chromatography at 30–36 d postpartum. Maternal intake of foods, nutrients, and dietary supplements was estimated using a food-frequency questionnaire. Linear regression models were established using xanthophylls, maternal diet, and sociodemographic factors. Xanthophyll concentrations were measured in human milk from 118 mothers. The xanthophyll concentration varied among individuals. The median (IQR) concentrations of lutein, zeaxanthin, and β-cryptoxanthin were 65.6 ng/mL (51.6–103.4 ng/mL), 18.6 ng/mL (12.9–25.8 ng/mL), and 15.6 ng/mL (9.0–26.0 ng/mL), respectively. In multivariate models, the lutein concentration was associated independently with dietary green vegetables, exclusive breastfeeding, and education (r2 = 0.153 for the model; β ± SE: 0.468 ± 0.198, 25.048 ± 10.222, and 13.460 ± 6.774; standardized β = 0.210, 0.217, and 0.175; P = 0.019, 0.016, and 0.049 for dietary green vegetables, exclusive breastfeeding, and education, respectively). For zeaxanthin, exclusive breastfeeding was the most appropriate predictor (r2 = 0.085; β ± SE: 7.811 ± 3.300; standardized β = 0.218; P = 0.020). The highest predictive power for human milk β-cryptoxanthin was obtained with dietary β-cryptoxanthin (r2 = 0.258; β ± SE: 0.089 ± 0.015; standardized β = 0.468; P < 0.001), attributed to maternal citrus intake. β-Cryptoxanthin in human milk was the xanthophyll most influenced by the maternal diet in Japanese women. The β-cryptoxanthin concentration in human milk was reflected by the maternal β-cryptoxanthin intake, mainly attributed to Japanese citrus consumption. This trial was registered in the Japanese Clinical Trials Registry (https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000017649) as UMIN000015494. β-Cryptoxanthin in human milk, the xanthophyll most influenced by the maternal β-cryptoxanthin intake, is mainly attributed to Japanese citrus consumption.