Related Experiment Video
Updated: Aug 19, 2025
07:38
Milk Collection in the Rat Using Capillary Tubes and Estimation of Milk Fat Content by Creamatocrit
Published on: December 16, 2015
12.5K
Vitamin A Concentration in Human Milk: A Meta-Analysis
Huanmei Zhang1,2, Xiangnan Ren1,2, Zhenyu Yang1,2
1Department of Maternal and Child Nutrition, National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Nutrients
|November 26, 2022
Summary
Human milk vitamin A (VA) levels decrease significantly throughout lactation. This meta-analysis provides crucial data for revising infant dietary reference intakes (DRIs) for better infant nutrition.
Area of Science:
- Human milk composition
- Nutritional science
- Lactation studies
Background:
- Vitamin A (VA) is essential for human health, yet international data on its concentration in human milk is scarce.
- Existing data offers limited support for revising dietary reference intakes (DRIs) for infants under six months.
- Understanding VA dynamics in breast milk is critical for optimizing infant nutrition.
Approach:
- A comprehensive literature review and meta-analysis of 76 studies (9171 samples) published between 1985 and 2021.
- Included studies focused on nursing mothers (18-45 years) with healthy, full-term infants, using HPLC/UPLC methods for retinol quantification.
- Data was synthesized using a random-effects model to analyze VA concentration across lactation stages.
Key Points:
- Human milk vitamin A concentration significantly declines as lactation progresses.
- VA levels (µg/L) at different lactation stages: colostrum (920.7), transitional (523.7), early mature (402.4), and late mature (254.7).
- No significant differences in VA concentration were found between Chinese and non-Chinese samples at any lactation stage.
Conclusions:
- The study provides robust evidence on the decline of vitamin A in human milk over time.
- Findings have significant implications for the potential revision of DRIs for infants under six months.
- This research contributes valuable data for public health recommendations concerning infant nutrition and VA intake.
Related Concept Videos
01:23Role of Skin in Vitamin D Synthesis
5.4K
The skin plays a crucial role in the synthesis of vitamin D, a vital nutrient for various physiological processes in the body. Vitamin D is unique because it can be synthesized in the skin through a series of chemical reactions triggered by exposure to ultraviolet B (UVB) radiation from sunlight.
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin...
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin...
5.4K
01:15Transcytosis of IgG
2.8K
Transcytosis is the process in which molecules are internalized by endocytosis, transported across the cell, and released through exocytosis from the opposite end of the cell. Molecules such as insulin, immunoglobulins, and certain nutrients are transferred through the recycling endosomes by recycling and transcytosis.
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
2.8K