Author: Rositsa Tashkova, Master of Molecular Biology and Microbiology

Playing in nature for a healthy immune system

It is known that children who live in modern societies and in urban environments suffer more often from autoimmune diseases, asthma, allergies, atopic dermatitis, than children who live closer to nature. There are many reasons for this, but one of them seems to be closely related to the microbiome and its role in the functions and maturation of the immune system. The microbiome is the collection of microorganisms that inhabit our body, but mainly the skin and our intestinal tract.

You can learn more about it from the articles The GI microbiome and our health and The GI microbiome is extremely important for you and your baby.

Of course, it would not be possible for all families with children to leave the cities and live in the country, but there is much we can do to provide our children with better health.

This autumn, a study by Swedish scientists from the University of Helsinki was published in the journal Science Advances [ref.1], which decided to conduct the first-of-its-kind study involving humans, in which the biodiversity of the urban environment has changed and the effects of this on the microbiome and immunoregulation in children have been studied.

The experiment lasted 28 days, with scientists tracking how the composition of microorganisms inhabiting children's skin and intestines would change and what would happen to some immunological markers in their blood.

The study involved 75 children between the ages of 3 and 5 from three different types of kindergartens - standard "urban" establishments, nature-oriented, and standard, but amended into a "natural" type specifically for the study.

10 kindergardens took part in the experiment and 4 of them transformed their playgrounds into something resembling the biodiversity of the forest areas - with the typical forest soil and grasses. Three of the others were originally designed in this way, and the other three - in a modern urban style.

After just a month, the scientists found that the microbiome of children in the first group resembled that of children who normally attended natural-type kindergardens. Moreover, the ratio of anti-inflammatory to pro-inflammatory markers in children's blood has changed in a way that shows improved immune function.

In conclusion, the researchers write: "Our findings suggest that intervention in biodiversity improves immunoregulatory pathways and provides an incentive for future preventive approaches to reduce the risk of immuno-mediated diseases in urban societies."

The factors that affect our microbiome are many - food, lifestyle, excessive use of disinfectants in the home, the environment in which we live. It seems that the diseases of the "modern man" go hand in hand with his poor microbiome. And it affects not only the functions of our immune system, but even those of the nervous system, and perhaps some aspects of our character and personality [ref.2] that we would never attribute to the invisible to the naked eye, but our eternal companions - bacteria.

More and more studies are emerging that show the relationship between the composition of the microbiome and psychological problems such as anxiety, depression, aggression [ref.3]. Scientists have even hypothesized the mechanism by which this occurs, with one hypothesis being that the hypothalamic-pituitary-adrenal axis plays a role [ref.4] - part of the neuroendocrine system that regulates various processes related to the action of hormones.

Microbiome and immune system

But let's go back to the practical application of this knowledge. How to provide a healthy microbiome to our children and ourselves, except by spending more time and play in nature:

  • Through food rich in fiber - bacteria in the large intestine break them down by fermentation and release short-chain fatty acids, which lowers local pH, and this in turn suppresses some disease-causing bacteria and favors the development of others - useful ones. [ref.5]
  • By intake of fermented foods - yogurt, kefir, sauerkraut, pickle obtained by natural fermentation (not by adding vinegar or other substances). Read more in the article Health benefits of fermented foods - the natural probiotics.
  • Breastfeeding for at least 6 months - the microbiome of babies and young children up to 2 years of age differs depending on whether they are breastfed or not. In breastfed children, there is a greater amount of beneficial bacteria called bifidobacteria, which help break down carbohydrates in milk. It has also been found that children who have not been breastfed are at higher risk of obesity, diabetes, leukemia, allergies, and there are risks for women who have not breastfed [ref.6]. It is possible that at least some of these conditions in children are related to the suboptimal microbiome.

So, if you can't move to live in nature, then you can try to move nature to yourself. For both every good thing and for our health and that of our children, effort is required, but it will be rewarded.

 

References:

  1. Biodiversity intervention enhances immune regulation and health-associated commensal microbiota among daycare children, Science Advances, 2020
  2. Gut microbiome composition and diversity are related to human personality traits, Human Microbiome Journal, 2020
  3. News Feature: Microbes on the mind, Proc Natl Acad Sci USA, 2015
  4. Gut microbiota regulates mouse behaviors through glucocorticoid receptor pathway genes in the hippocampus, Transl Psychiatry, 2018
  5. The Microbiome, www.hsph.harvard.edu/nutritionsource/microbiome/
  6. The risks of not breastfeeding for mothers and infants, Reviews in obstetrics & gynecology, 2011

 

The author:

👩 🔬 Rositsa Tashkova-Kacharova has a Bachelor degree in Molecular Biology and a Master's degree in Microbiology and Microbiological Control. She completed her Master's thesis at the University of Nantes, France. At that time she painted a Christmas tree of bacteria and inspired the announcement of the first competition for drawing with microorganisms Agar Art. For 3 years she was the editor of the journal Bulgarian Science and continues to write about science and medicine.