Not only are they good but they seem actually essential!
Studies on very large numbers of children show clearly that those who are able to play in a rural and green environment are healthier for it. It’s all about mud!
These observations have been published in major peer reviewed medical and scientific journals and here are some examples:
- A Swedish study looking at just over 1 million children (yes – One Million!), showed that exposure to dogs and farm animals reduced the risk of asthma by the age of six years. (Published in the Journal of the American Medical Association Paediatrics in 2015).
- A Danish study on over 800,000 children showed that ADHD (Attention Deficit Hyperactivity Disorder) risk was far lower in those brought up in areas with access to green areas, such as city parks, than otherwise. (Environmental Health Perspectives Journal in December 2020).
- A Finnish study on children’s playgrounds showed that changing a concrete surface to one composed of natural forest floor material positively enhanced their microbiome and their immune regulation. (Science Advances October 2020)
- A German study comparing urban and rural living and the effect on social stress on their immune system clearly demonstrated that those from a rural environment and who worked with animals did far better. (Proceedings of the National Academy of Science 2018).
- A US study comparing immune responses and asthma rates in children from Amish and Hutterite communities was especially fascinating and important. The Amish lead a more traditional rural life with more exposure to animals than the Hutterites who embrace more modern technology and do not allow pets in the home. The researchers swapped dust from their households and looked also at animal models and were able to show that the Amish had better innate immune responses and less asthma. (New England Journal of Medicine in 2016).
- A similar study from Finland and Germany swapped dust from a farm like environment to rural homes had a similar effect, so the benefit is indeed transferable and real.(Nature Medicine 2019).
The Australians need no convincing in that many schools now encourage outdoor learning and have noted a dramatic fall in classroom violence, misbehaviour and suspensions. Many other countries including the UK are also beginning to promote outdoor schooling, perhaps a silver lining to the COVID pandemic!
Where do mycolicibacter fit in?
All these studies have focused on bacterial diversity and those that tend to live and multiply on the skin and in the gut (the Microbiome). For sure, diversity is the key and there is no single “magic” organism that is the answer.
Mycolicibacter are transient commensals to the microbiome – this means that they do not live on or in us but pass through on a regular basis as and when they are ingested. They do not colonise the gut or skin. However, their presence in the environment and especially mud and soil, makes them important players in the equation because of their special effect on immunity. Most are harmless but some are not. In addition, they all have different effects on immune responses, whereas we know far more about the safety and action of aurum.
We have mentioned before that other agents in soil and water, such as helminths (worms) and other, potentially harmful, bacteria also help to “tune” immunity and form part of the basis for the Old Friends Hypothesis. We do not want to risk any bad effects and who wants to eat worms anyway?!
Aurum was present in the natural environment and we know that replacing it when exposure has been lost is an important factor in maintaining a strong immune system. Doing so in a safe and controlled manner has to be a sensible way forward.