An research from Henry Ford Hospital supports the theory that a sterile environment is not good for babies. This research reveals that Breastfeeding It is one of the most effective ways to stimulate babies immune systemThe study also explains why breast milk helps reduce susceptibility to allergies and asthma through the changes it promotes in the intestinal bacteria of the baby.
This in itself is nothing new. But the research shows solid findings thanks to a series of studies on the so-called hygiene hypothesis, which explains how the early exposure to microorganisms During childhood it affects the development of the immune system and the appearance of allergies, according to the main author of the work, christine cole johnson, director of the Department of Public Health Sciences at Henry Ford. I can tell you in advance that living with a dog It is, along with breastfeeding, another way to promote immune maturation of the baby.
Early microbiome and the "hygiene hypothesis": what we know today
El gastrointestinal tract of the baby contains a bacterial ecosystem which plays a crucial role in the immune system training and has been linked to diseases such as obesity, autoimmune diseases, circulatory disorders, pediatric allergies and infections. "For years, we've always thought that a sterile environment wasn't good for babies. Our research shows why. Exposure to microorganisms in the first few months after birth helps stimulate the immune system."explains Christine Cole Johnson. "The immune system is designed to be exposed to bacteria on a large scale. If these exposures are minimized, it will not develop optimally.".
Today, thanks to the science of microbiome, we better understand this critical window. There is debate about whether the uterus is sterile or not. Some work with DNA sequencing has suggested the presence of Bacterial DNA in placenta, amniotic fluid and meconium, and that metabolites such as short chain fatty acids could influence the developing fetal immune system. However, closely controlled reviews indicate that many detections may be due to contamination of samples or reagents. With the available knowledge, the balance leans towards the Microbial colonization begins mainly at birth (vaginal contact or skin contact in cesarean section), the technology and, most especially, the lactationThis clarification is important to understand where we should place our practical focus.
In addition, the maternal immunization and the transfer of IgG antibodies through the placenta, as well as the Milk IgA, contribute to protecting the newborn during this period of high susceptibility of the first months. In addition, the maternal-fetal microchimerism as a possible pathway for immunological "instruction." All of this fits with the idea that the baby needs safe and guided exhibition to beneficial microbes, not absolute sterilization of their environment.
Factors that shape the baby's microbiome
In six separate studies, researchers assessed whether Breastfeeding had an effect on the intestinal microbiome of the baby and its relationship with allergies and asthma. They were analyzed stool samples at one and six months and studied whether the microbiome influences the development of the regulatory T cells (Treg), key to regulating the immune response. Breastfed babies showed distinct microbiome compositions to those of non-breastfed individuals, with differences that may modulate immune maturation.
The researchers found that microbiome patterns of the baby vary depending on multiple factors: type of delivery (cesarean vs. vaginal), gestational age, prenatal and postnatal exposure to tobacco smoke, ethnic roots of the mother, use of antibiotics y presence of domestic animals at home. For example, the exposure to dogs or cats during the first year is associated with a lower risk of allergies in various studies conducted by Henry Ford teams and other groups.
Beyond the house, the contact with natural environments, the interaction with hermanos and assistance to creche They also expand the diversity of environmental microbes. The message is not to "make things dirty for the sake of making them dirty," but to allow for a normal microbial strain typical of everyday life, avoiding the constant sterilization from the baby's environment.
Breastfeeding, Tregs, and the risk of allergies and asthma
Breastfed babies in the first month showed lower risk of pet allergies and, among those diagnosed with asthma with cough and night attacks, a different intestinal composition during the first year. It is therefore demonstrated that the composition of the intestinal microbiome is associated with the increase in Treg cells, which helps modulate inflammation and immunological tolerance.
Breast milk provides IgA antibodies, antimicrobial factors, oligosaccharides (HMOs) that feed beneficial bacteria, immune cells and bioactive components that cooperate in the development of mucous barriers and the immune balanceThis biological "toolbox" explains its ability to reduce infections gastrointestinal and respiratory diseases and to cushion the risk of allergies.
In parallel, the maternal immunization During pregnancy, in accordance with current health recommendations, it enhances the transfer of protective antibodies to the baby and can shorten the so-called "immunological gap» of the first months. The combination of lactation, recommended vaccination y normal environmental exposure It sets up a coherent strategy to strengthen defenses without resorting to extreme sterilization.
Pets, environment and everyday exhibitions
"Research tells us that exposure to a higher and more diverse load of environmental bacteria and specific patterns of gut bacteria appears to boost the immune system's protection against allergies and asthma.", concludes Dr. Johnson. Living with Pets (especially dogs), perform Outdoor Activities and allowing the baby to safely explore its environment promotes that early microbial "catalogue" that the immune system needs to learn to distinguish friend from enemy.
Now, everything must be done with common sense: the useful exposition is the everyday and safe, not contact with sources of contamination o health risksThis involves taking care of the air quality, avoid the smoke of the tabacco, ventilate the house, maintain the daily vaccination and use antibiotics only when indicated by health professionals.
Always clean, but without going overboard
That obsession with the cleaning and sterilization It's more of a need created by advertising than a real need, I think. How would children be raised in the past, when they lived with livestock and hygiene was not, by any means, what it is today? We agree that Child mortality It was very high (and so was the birth rate, by the way). Applying Darwin's principles of evolutionism, the fittest survived. So what kind of children are we raising now?
Fortunately, we now have resources so that we do not have to subject our children to a "natural judgment", but disservice we do to them if we do not let them develop their own defensesThe key is a reasonable balance between hygiene and normal exposure. Some practical guidelines:
- Basic daily hygiene: hand washing before eating, after bathing, and after changing diapers; it's not necessary to disinfect every surface several times a day.
- Disinfect judiciously: when there is vomiting, heces o contagious disease at home, and in areas of food preparation.
- Avoid antibacterial products routinely; plain soap and water are usually sufficient for everyday cleaning.
- Outdoor life and contact with nature y Pets under basic safety and hygiene standards.
If my experience is of any help, I have breastfed three children. And the one who is least sick is put is the one more time was sucking. And he's also the one who's been in contact with animals longer and from a younger age. This is a personal testimony, not scientific proof, but it does fit with what we know today about microbiota and immune development.
After birth, the newborn passes from a nearly sterile environment to the outside world. During this transition, their immune system goes from a more tolerant towards one of progressive activation, with the support of the maternal antibodies transferred by the placenta and reinforced by the lactation. For a few months there is a window of greatest susceptibility, which is best handled with Breastfeeding, hygiene with common sense, recommended vaccination, and avoiding both exposure to smoke such as the unnecessary use of antibioticsLiving with a normal microbial diversity and safe not only supports the protection of the baby: it is an active part of its immunological maturation.
