Breast milk breastfeeding promotes the immune system

Breastfeeding has a positive effect on the immune system

09/04/2014

Breastfeeding is the best nutrition for a baby because breast milk contains all the nutrients the child needs during the first few months of life. But not only that, because the milk also contains important antibodies that stimulate the baby's immune system and make it more resistant to certain diseases. How this works exactly was not yet clear among experts. However, Californian researchers have now put forward a new theory, according to which apparently the intestinal flora of the child plays a central role.

Breast milk is considered ideal food for infants
Midwives and paediatricians recommend women to nurse their babies again and again. Not without reason, since breast milk is considered by experts to be the ideal food for a baby because it contains all the important nutrients such as proteins and fatty acids. In addition, it protects the newborn from pathogens, because the milk contains a variety of antibodies that stimulate the immune system and thereby strengthen the child's resistance to certain diseases. How exactly these processes proceed, however, was not clarified among experts so far.

California scientists examine newborn rhesus monkeys
But now scientists from the „California National Primate Research Center (CNPRC)“ The University of California at Davis (USA) and the University of California at San Francisco have developed a new theory. According to this, the positive effect of breastfeeding on the immune system of the child is apparently achieved via the intestinal flora - which even then stops when the child has long been weaned from the breast. The researchers around Dennis Hartigan-O'Connor came to this conclusion by a study of newborn rhesus monkeys, half of which was breastfed for six months, the other group got milk from the bottle.

Less bacterial diversity in bottle-fed animals
Following this, all animals were fed the same food for another six months - but after that time there was an amazing effect: the monkeys who had been breastfed had a varied intestinal flora with plenty of Prevotella and Ruminococcus bacteria after breastfeeding , which persisted even after the six month follow-up. The other group, on the other hand, showed a large amount of clostridium, which means „bottle-fed animals [.] less wealth, uniformity and variety of bacteria“ had the report of the researchers in the journal “Science Translational Medicine”. The differences had intensified over time, „indicating a lasting influence of the initial microbial colonization on the intestinal flora.“

Significant differences also in the influence of the intestinal flora on the immune system
In addition, the scientists studied the influence of the intestinal flora on the immune system, which also showed significant differences between the two groups: „We were able to see the development of two different immune systems: one, the animals fed breast milk, and one of those who had breastmilk substitutes“, said Dennis Hartigan-O'Connor in a CNPRC statement. „But the most amazing thing is the permanence of these differences. The intestinal flora could leave a lasting impression on the immune function in infants“, Hartigan-O'Connor continues.

„A programming of the system“
Particularly striking is the difference in the proportion of so-called „Th17 cells“ which is called helper T cells that produce the messenger interleukin 17 (IL-17). „The percentage of CD4 helper cells producing interferon (IFN) and IL-17 on stimulation was on average 15 fold higher in breastfed infants compared to bottle-fed monkeys”, the researchers write. An interesting result, as these differences could potentially impact on immune responses and susceptibility to autoimmune diseases. „This study indicates that the intestinal flora in the first few months of life has a lasting influence on the shape and function of the immune system - a programming of the system, if you will“, adds Amir Ardeshir of the CNPRC. Also for Professor Tim Niehues of the Helios Institut Krefeld the new investigation should be regarded as very differentiated and careful. Nevertheless, it is difficult to translate the results directly to the differences between breastfeeding and replacement diets, since, for example, the influence of subclinical infections can not be ruled out, according to the expert in pediatric immunology „world“. (Fp)