358 - Comparing free choline in human milk and the maternal diet of term infants

Publication Number: 3345.358

Carli Edwards, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Katherine Chetta, Medical University of South Carolina College of Medicine, Charleston, SC, United States; John E. Baatz, Medical University of South Carolina, Charleston, SC, United States; Danforth A. Newton, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Lakshmi D. Katikaneni, Shawn Jenkins Children’ s Hospital, Charleston, SC, United States; Carol L. Wagner, Medical University of South Carolina, Charleston, SC, United States

Background: Choline is an essential nutrient for cellular function with key roles in infant neurodevelopment. Human milk is uniquely rich in bioavailable choline. However, variability in human milk choline content and its relationship to maternal diet and infant health outcomes remain poorly understood. Limited evidence suggests that maternal diet may affect human milk choline content.

Objective: We investigated associations between maternal dietary intake and free choline concentrations in human milk and serum at 1 and 4 months postpartum in mothers delivering ≥35 weeks with exclusive breastfeeding. We hypothesized that there would be significant variability in the human milk choline concentration at 1 and 4 months’ postpartum that would positively correlate with maternal dietary choline intake.

Design/Methods: Human milk and maternal serum samples were collected at 1 and 4 months postpartum from 58 mothers of healthy, term infants participating in a lactation immune pilot study. Free choline was measured using a fluorescence-based assay (Abcam, ab219944). Maternal dietary intake was estimated from a validated food frequency questionnaire obtained at 2 months postpartum. Choline concentrations were summarized with mean and standard deviation. Spearman’s correlation was used to correlate maternal dietary intake estimates and human milk concentrations (p < 0.05).

Results: 64 human milk samples from 32 of 58 subjects have been analyzed. Free choline in human breast milk had a mean of 13.8 mg/L ± 4.9 mg/L in all patients, varying widely (2–25 mg/L). While 16 women showed increases in free choline from early to later lactation, 16 showed declines. Median breast milk choline concentrations of mothers at 1 and 4 months postpartum were similar, but inter-individual variability was high. Maternal serum free choline concentrations (0.2–1.6 mg/L) were consistently lower than milk concentrations. Spearman’s correlation revealed no association between free choline in human milk samples and reported choline intake. No significant correlation was observed between estimated dietary choline and maternal serum free choline.

Conclusion(s): Human milk free choline concentrations varied considerably between mothers and across time and were not strongly correlated to dietary intake or serum levels. This highlights the need for further investigation of factors that affect the content of free choline in human milk. Larger sample sizes will be necessary to determine smaller effect sizes and to investigate whether other maternal, genetic, or environmental characteristics contribute to the variable concentrations of free choline in human milk.