Transfer of selected elements from food into human milk

Area of Science:

• Environmental Science
• Human Nutrition
• Analytical Chemistry

Background:

• Breast milk composition is crucial for infant nutrition and development.
• Understanding elemental transfer from maternal diet to milk is vital for assessing infant exposure.
• Variability in maternal diet and physiological factors can influence nutrient bioavailability.

Purpose of the Study:

• To measure the transfer factors of 13 essential and trace elements from food to breast milk in nursing mothers.
• To investigate the variability of these transfer factors among individuals.
• To provide data for assessing infant exposure to dietary elements through breastfeeding.

Main Methods:

• Collection of daily food and milk samples from 19 nursing mothers over 2 to 8 weeks.
• Analysis of elemental content using microwave-assisted pressure digestion and inductively coupled plasma mass spectrometry.
• Calculation of transfer factors (element concentration in food divided by concentration in milk).

Main Results:

• Transfer factors varied significantly across elements, with molybdenum (77.4) and gallium (19.1) showing higher values.
• Significant inter-individual differences in transfer factors were observed for all measured elements.
• Ruthenium (4.1) and silver (5.1) exhibited the lowest transfer factors.

Conclusions:

• Observed differences in breast milk elemental levels are likely due to individual variations in milk production and absorption, not solely dietary intake.
• Maternal physiological factors play a significant role in determining the elemental composition of breast milk.
• Further research is needed to elucidate the precise mechanisms behind inter-individual variability in elemental transfer.