Optical Analysis of Human Milk Offers Recent Insights into Lactation and Infant Health

Researchers at the University of Twente in the Netherlands are pioneering new methods for analyzing human milk using optical techniques, potentially leading to better understanding and support for breastfeeding mothers. The work, published in Biophotonics Discovery, focuses on the light-scattering properties of milk to determine its composition, particularly fat content, in a non-invasive way.

The Challenge of Lactation Insufficiency

Many mothers face challenges with initiating and maintaining breastfeeding. Between 40 and 60 percent of mothers may discontinue breastfeeding due to the perception of insufficient milk supply. However, studies suggest that actual lactation insufficiency affects 10 to 15 percent of mothers, and the underlying causes remain largely unknown. Objective methods for measuring milk composition are crucial to addressing this issue.

How Light Scattering Reveals Milk Composition

The research team discovered that the way light scatters when passing through human milk provides a wealth of information about its composition. Specifically, fat content – the primary source of energy in milk – is a key indicator of adequate milk production. Changes in fat concentration can be predictive of successful breastfeeding.

Refractive Index: A Key Measurement

A collaborative study with the University of Amsterdam, detailed in Biophotonics Discovery, focused on determining the refractive indices of particles within human milk that cause light scattering. This is the first study of its kind. Understanding the refractive index of milk fat globules (MFGs) and extracellular vesicles (EVs) is essential for accurate interpretation of data from optical methods like laser diffraction analysis.

Researchers used flow cytometry to assess the refractive index distribution of MFGs and EVs, finding qualitative differences between human and cow’s milk. The study highlighted that using bovine MFG refractive index values in laser diffractometry can lead to significant errors due to differences in fatty acid composition between the two species.

Modeling Light Scattering Behavior

The second study at the University of Twente utilized the refractive index data to model the light scattering behavior of human milk. It found that light scattering is influenced not only by fat concentration but likewise by the size distribution of fat particles within the milk. This suggests a more complex relationship between milk composition and optical properties than previously understood.

Future Implications for Breastfeeding Research

These findings pave the way for improved light scattering-based methods for analyzing human milk. Such techniques offer the potential for compact, fast, and non-invasive analysis while preserving the milk for infant consumption. Inline monitoring of changes in milk composition during a single breastfeeding session could provide a powerful tool for in-depth research into lactation insufficiency.

The researchers emphasize that the established dataset of human milk optical properties can be expanded and utilized in future studies to support the development of optics-based measurement systems and further research on breastfeeding using non-invasive methods. As reported by Optics.org, this research represents a significant step towards objective and noninvasive milk composition analysis.