Use of Compartmental Modeling and Datasets for Theoretical Lactating Women to Determine Conditions under Which Vitamin A-Specific Activity in Breast Milk Provides Accurate Estimates of Vitamin A Total Body Stores by Retinol Isotope Dilution

Michael H. Green*, Veronica Lopez-Teros, Jessica Avila-Prado, Joanne Balmer Green

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

Background: Vitamin A concentrations in breast milk are related to maternal vitamin A intake and status. Objectives: Our objective was to identify conditions under which vitamin A specific activity in breast milk (SAm) could be used instead of retinol specific activity in plasma (SAp) to predict vitamin A total body stores (TBS) by retinol isotope dilution (RID). Methods: We used 12 previously-studied theoretical lactating women with assigned values for TBS (219-1348 μmol) and retinol kinetic parameters; we assumed subjects ingested a dose of stable isotope-labeled vitamin A. We expanded a 9-compartment steady state tracer model to include a parallel model for tracee (unlabeled retinol) and then adapted that model so vitamin A intake entered the system in 3 meals each day. Using compartmental analysis, we first simulated SAm and SAp after an overnight fast (as in actual RID experiments) and then with vitamin A intake also restricted in sequential meals on the day before sampling for RID. Results: After an overnight fast, SAm at day 21 postdosing was lower than SAp. However, if vitamin A intake was also restricted in 1, 2, or 3 meals before sampling, SAm/SAp (mean ± SD) was 0.92 ± 0.042, 0.96 ± 0.016, or 0.99 ± 0.004, respectively; results for days 14 and 28 were similar. When either SAp or SAm was used to predict TBS by RID on day 21 after 1-d restriction, predictions for all subjects were within 25% of assigned TBS. Conclusions: Results indicate that, for theoretical lactating women with a wide range of vitamin A status, SAm will accurately predict TBS by RID at 2-4 wk postdosing if vitamin A intake is restricted for 1 d before sampling. If confirmed in community settings, results suggest that vitamin A status in lactating women can be determined without collecting blood.

Original languageEnglish
Pages (from-to)1629-1634
Number of pages6
JournalJournal of Nutrition
Volume152
Issue number7
DOIs
StatePublished - 1 Jul 2022

Bibliographical note

Publisher Copyright:
© 2022 The Author(s). Published by Oxford University Press on behalf of the American Society for Nutrition.

Keywords

  • model-based compartmental analysis
  • retinol isotope dilution method
  • theoretical lactating women
  • vitamin A during lactation
  • vitamin A status

Fingerprint

Dive into the research topics of 'Use of Compartmental Modeling and Datasets for Theoretical Lactating Women to Determine Conditions under Which Vitamin A-Specific Activity in Breast Milk Provides Accurate Estimates of Vitamin A Total Body Stores by Retinol Isotope Dilution'. Together they form a unique fingerprint.

Cite this