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Circadian Variation in Human Milk Hormones and Macronutrients
Majed A Suwaydi1,2, Ching Tat Lai1, Alethea Rea3
1School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
Nutrients
|September 9, 2023
Summary
Daily variations in human milk (HM) components like hormones and macronutrients are not well understood. This study reveals significant within-feed and circadian changes, highlighting the need for standardized collection methods for accurate infant health research.
Area of Science:
- Human milk composition
- Endocrinology
- Nutritional science
Background:
- Inadequate understanding of daily variations in human milk (HM) hormones and macronutrients.
- Inconsistent sample collection protocols across studies hinder accurate analysis.
Purpose of the Study:
- To investigate diurnal variations in HM components and infant intake.
- To assess within-feed and circadian changes in HM composition.
- To inform standardized sampling procedures for HM research.
Main Methods:
- 22 lactating women collected milk samples over 24 hours.
- Test weighing determined milk volume consumed per feed.
- Concentrations of leptin, adiponectin, insulin, fat, and glucose were measured.
Main Results:
- Significant differences in pre-feed and post-feed concentrations for adiponectin, glucose, insulin, and fat.
- Circadian rhythms observed in leptin, adiponectin, insulin, glucose, fat concentration, and milk volume.
- Average infant intake of HM was 879 g/24 h.
Conclusions:
- Human milk composition exhibits significant within-feed and circadian variations.
- Standardized, rigorous sampling protocols are essential for precise understanding of HM's impact on infant health.
- Accurate assessment requires consideration of diurnal fluctuations in HM components.
Keywords:
adipokinebreastfeedingcircadian rhythmdiurnal rhythmhormoneshuman milklactationmacronutrientMore Related Videos
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