3 Fascinating Facts About Breast Milk Fats

April 12, 2020
Breast milk fats are transported packages in fat globules. These "packages" are effective carriers of energy in the form of triglycerides. But they also carry fat-soluble substances that are of vital importance to the infant.

Breast milk fats have functions beyond simple nutrition. Milk is a living, changing tissue and, as such, its composition isn’t uniform. Amazingly, its components vary throughout the day and between feeds. It also changes gradually according to the age of the baby.

Although the mother’s diet isn’t a determining factor in these changes, some nutrients can be affected by maternal intake. In general, the composition of a mother’s milk is specifically tailored to the developmental needs of her baby. This is true at every stage of growth, including the needs of premature babies.

The energy content of breast milk is obtained primarily from two components. The first, lactose, is the most abundant component in the milk. The other component is the fat that’s present in the breast milk.

It’s interesting to remember that, along with milk fat, our body also transmits fat-soluble molecules. For example, vitamins A, D, E, K, and other carotenoids. Today we’re going to talk about three interesting facts about these breast milk fats.

A woman breast feeding.

1. Breast milk fats are dispensed in an emulsion

Milk is an emulsion, with fat particles, known as fat globules, dispersed in a watery liquid (whey). The cells of the breast epithelium produce these fat globules. They come in different sizes, with diameters ranging from 0.1 to 10 microns.

In terms of their composition, they contain substances that are characteristic of the mammary epithelial cells. Scientists have discovered that these have a high proportion of triglycerides. However, their primary feature is that they’re covered by a uniquely-structured membrane, known as the milk fat cell membrane.

Why does this membrane matter?

It’s very interesting to know that this membrane has three layers of phospholipids, when in the rest of the body it only has two. Thanks to this unique structure of the membrane, the fat globules don’t bind to each other and the fat particles stay separate from the watery substance.

In addition, the structure and composition of this membrane allows it to transport metabolically-important lipids, such as sphingomyelin and gangliosides. At the same time, the milk fat cell membrane is a source of many other bioactive compounds. These include glycolipids, glycoproteins and carbohydrates, which have important functions to carry out in the brain, the gut and the immune system.

2. Fat globules in breast milk affect the development of intelligence

The membrane lipid components of the fat cell, such as sphingomyelin and gangliosides, are highly concentrated in the brain. Experts have discovered that they help the formation of the connections (synapses) between neurons and also the creation of myelin.

Myelin is important because it acts as the axons’ insulator, resulting in a more efficient transmission of the nerve impulses. Myelinization is a process that accounts for a large part of brain growth during late gestation and the first two years of life. However, this process can also continue until a child is 5, or even up to 10 years of age.

Researchers have carried out several clinical trials in children ranging from premature infants to preschoolers. They showed that dietary supplementation of the milk fat cell membrane improves cognitive process and behavior.

3. Breast milk fats strengthen the immune system and promote intestinal health

Studies in animals have shown that gangliosides strengthen the immune system. In addition, other components transported by fat globules also affect the immune response. Such components include different proteins, such as lactadherin, mucin-1 and butyrophilin.

Each of these influences the immune system through several different processes. For example, they can interfere with the adhesion of pathogenic microbes to the intestinal epithelium. Others have a bactericidal action and may even help the development of the intestinal microbiota.

We hope this article has shown you the amazing properties of breast milk and how it influences a child’s growth in many different ways!

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