The Protective Properties of Lactoferrin for Your Baby
During lactation, lactoferrin mediates the absorption of iron, the fight against bacteria and other pathogens, and the modulation of the immune response.
Lactoferrin is one of the most abundant proteins in breast milk. There’s a good reason for this: it acts on several fronts that all contribute to the baby’s immunity. In this way, it prevents infection, mediates iron metabolism, has anti-inflammatory properties, and is an antioxidant.
Let’s imagine that breast milk is like an army. The fluid contains a variety of fighters who are specially trained in different germ-killing strategies.
Some components, like an army corps of engineers, build the infrastructure, helping the maturation of intestinal tissue. In this context, lactoferrin would qualify as one of the generals of the breast milk army. Today we’re going to talk about this multifaceted protein.
Why is iron important?
Iron is a vital element, not only for mammals, but also for bacteria. It’s a key component in such important processes as the transporting of oxygen, nitrogen fixation, and other enzymatic reaction systems. In milk, iron doesn’t travel on its own; it travels in tandem with lactoferrin.
It’s important to emphasize that the iron contained in breast milk has a high bioavailability, which means that a baby absorbs it in a high proportion. This is due to several factors, such as the higher acidity of the baby’s gastrointestinal tract, and the presence of appropriate levels of zinc and copper.
In addition, iron has a special ally: lactoferrin. The system works as follows: intestinal cells have specific receptors for lactoferrin on their surface, and only when lactoferrin-receptor coupling occurs is iron released into the cell.
Thanks to this protein, the baby absorbs 70% of the iron contained in human milk. In contrast, if it ingests lactoferrin from cow’s milk, it absorbs only 30%.
Iron retention as a defense against infection
The best-known role of this protein in infant defense is as a bacteriostatic agent. Since many bacteria need iron to proliferate, lactoferrin competes with them. This means that it inhibits bacterial proliferation through its iron sequestering properties.
We should note that, in milk, lactoferrin can be found saturated with iron (with two iron molecules). It can also carry one iron molecule or none at all. Experts estimate that only 6-8% of milk lactoferrin is saturated with iron. Thus, as there’s so much “iron-free” lactoferrin, that means that a good proportion of this protein can exert the aforementioned sequestration.
Lactoferrin can kill a variety of microbes
Scientific reports have shown that this essential element can interact directly with the surface of pathogenic bacteria. They increase the permeability of the bacterial membrane and thus cause their death. Additionally, experts have reported that lactoferrin-derived peptides (fragments of the protein) can exert antiviral and antifungal effects.
Consistent with this antimicrobial effect, several clinical trials have shown that lactoferrin prevents diarrhea, neonatal sepsis, and necrotizing enterocolitis in preterm infants.
It also influences the maturation of the baby’s intestinal tissue
It’s important to remember that, at birth, the baby’s gastrointestinal system is immature. It’ll take about twelve months for all the organs to complete their development and reach optimal functioning. We know that lactoferrin, by determining the availability of iron, can affect tissue maturation.
Lactoferrin may exert an anti-inflammatory effect
As if that weren’t enough, this protein has a wider role in the body’s defense mechanism through its immunomodulatory actions.
One of the features of this protein is that it has a positively charged surface. Thanks to this, it has a favorable interaction with the surface of immune cells. This interaction can trigger signaling pathways, thus leading to anti-inflammatory responses.