Back
Full-text
Journal article

Breast Milk Iodine Concentration Is a More Accurate Biomarker of Iodine Status Than Urinary Iodine Concentration in Exclusively Breastfeeding Women.

  • Dold S Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland; susanne.dold@hest.ethz.ch.
  • Zimmermann MB Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
  • Aboussad A Mohammed VI University Hospital, Marrakesh, Morocco.
  • Cherkaoui M Laboratory of Human Ecology, Faculty of Sciences Semlalia, Cadi Ayyad University, Marrakesh, Morocco.
  • Jia Q Shanxi Institute for Prevention and Treatment of Endemic Disease, Linfen, China.
  • Jukic T Department of Nuclear Medicine and Oncology, School of Medicine, University of Zagreb, Zagreb, Croatia.
  • Kusic Z Department of Nuclear Medicine and Oncology, School of Medicine, University of Zagreb, Zagreb, Croatia.
  • Quirino A St. Luke's Medical Center, Quezon City, Manila, Philippines; and.
  • Sang Z Institute of Endocrinology, Tianjin Medical University, Tianjin, China.
  • San Luis TO St. Luke's Medical Center, Quezon City, Manila, Philippines; and.
  • Vandea E Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
  • Andersson M Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
Show more…
  • 2017-02-24
Published in:
  • The Journal of nutrition. - 2017
breast milk iodine concentration
breastfed infants
infancy
iodine
iodine deficiency
iodine status
lactating women
lactation
urinary iodine concentration
Adult
Biomarkers
Breast Feeding
China
Croatia
Cross-Sectional Studies
Female
Humans
Iodine
Milk, Human
Morocco
Nutritional Status
Philippines
Young Adult
English Background: Iodine status in populations is usually assessed by the median urinary iodine concentration (UIC). However, iodine is also excreted in breast milk during lactation; thus, breast milk iodine concentration (BMIC) may be a promising biomarker of iodine nutrition in lactating women. Whether the mammary gland can vary fractional uptake of circulating iodine in response to changes in dietary intake is unclear.Objective: We evaluated UIC and BMIC as biomarkers for iodine status in lactating women with a wide range of iodine intakes.Methods: We recruited 866 pairs of lactating mothers and exclusively breastfed infants from 3 iodine-sufficient study sites: Linfen, China (n = 386); Tuguegarao, Philippines (n = 371); and Zagreb, Croatia (n = 109). We also recruited iodine-deficient lactating women from Amizmiz, Morocco (n = 117). We collected urine and breast milk samples and measured UIC and BMIC.Results: In the 3 iodine-sufficient sites, a pooled regression analysis of the estimated iodine excretion revealed higher fractional iodine excretion in breast milk than in urine at borderline low iodine intakes. In contrast, in the iodine-deficient site in Morocco, a constant proportion (∼33%) of total iodine was excreted into breast milk.Conclusions: In iodine-sufficient populations, when iodine intake in lactating women is low, there is increased partitioning of iodine into breast milk. For this reason, maternal UIC alone may not reflect iodine status, and BMIC should also be measured to assess iodine status in lactating women. Our data suggest a BMIC reference range (2.5th and 97.5th percentiles) of 60-465 μg/kg in exclusively breastfeeding women. This trial was registered at clinicaltrials.gov as NCT02196337.
Language
  • English
Open access status
bronze
Identifiers
Persistent URL
https://sonar.ch/global/documents/168226
Statistics
Document views: 62 File downloads:
  • Full-text: 0