Abstract
Growing evidence indicates that human milk oligosaccharides (HMOs) are important bioactive compounds that enhance health and developmental outcomes in breastfed babies. Maternal dietary intake likely contributes to variation in HMO composition, but studies identifying diet-HMO relationships are few and inconsistent. This study aimed to investigate how the maternal intake of macronutrients and micronutrients-specifically proteins, fats, vitamins, and minerals-associated with HMOs at 1 month (n = 210), 6 months (n = 131), and 12 months postpartum (n = 84). Several associations between maternal dietary factors and HMO profiles were identified utilizing partial correlation analysis. For example, maternal free sugar (rho = -0.02, p < 0.01), added sugar (rho = -0.22, p < 0.01), and sugary sweetened beverage (rho = -0.22, p < 0.01) intake were negatively correlated with the most abundant HMO, 2'-fucosyllactose (2'-FL), at 1 month, suggesting that higher sugar consumption was associated with reduced levels of 2'-FL. Further, vitamins D, C, K, and the minerals zinc and potassium were positively correlated with 2'-FL at 1 month (p(All) < 0.05). For the longitudinal analysis, a mixed-effects linear regression model revealed significant associations between maternal vitamin intake and HMO profiles over time. For example, for each unit increase in niacin intake, there was a 31.355 nmol/mL increase in 2'-FL concentration (p = 0.03). Overall, the results provide additional evidence supporting a role for maternal nutrition in shaping HMO profiles, which may inform future intervention strategies with the potential of improving infant growth and development through optimal HMO levels in mothers' milk.