Open access research from frontiers in Psychology:
How might contact with nature promote human health? Promising mechanisms and a possible central pathway
“How might contact with nature promote human health? Myriad studies have linked the two; at this time the task of identifying the mechanisms underlying this link is paramount. This article offers: (1) a compilation of plausible pathways between nature and health; (2) criteria for identifying a possible central pathway; and (3) one promising candidate for a central pathway.
…enhanced immune functioning emerges as one promising candidate for a central pathway between nature and health. There may be others.”
A nice, easily read, review of the many beneficial effects of contact with nature. The review identified 21 possible pathways, proposed in the literature, by which contact with nature may have beneficial effects – benefits such as reduction in stress and anxiety disorders, reduced cardiovascular disease, reduced musculoskeletal complaints, and improved healing. The review then proposes that these multiple proposed pathways may all contribute to a single ‘central pathway’ – that of improved immune function, which then mediates the positive health effects.
Immune boosting behaviours
Another good reason to get outside and feel good in the sunshine, contact with nature probably also belongs on this list
Some recent studies of Amazonian tribes, living in remote areas, have stomach bacterial varieties up to ten times more varied than bacterial variety more common with demographics in populated, more medicated, areas. With the tribes, their general resistance to local threats, and their healing responses, are boosted by having such a varied bacterial source to call upon. However, they seemingly have little resistance to threats more common in populated areas, such as influenza, chicken pox etc etc. There might seem to be some trade-off in play, where living in populated areas actually helps decrease the bacterial varieties available, in favour of a dominance of particular bacteria which address diseases more common in populated areas.
I’m not sure that altering habitats, or ‘greening-up’, is the way to encourage a greater variety of bacterial protection in the ‘populated areas’ demographic. That, in theory, would be similar to Genetic Modification, which, surprisingly, can create greater vulnerability to , as yet, unknown threats. There is always a risk that exposure to new environmental influences can render previous default protections redundant. It’s a matter of how the immune system prioritises threats. Exposure and defense happen by default, usually. Meddling in that process might have a downside.
Thanks for your thoughts and comments. Interesting stuff there with the Amazonian tribes – have you got any references where we could read more? Is there any evidence that “living in populated areas decreases the bacterial varieties available, in favour of a dominance of particular bacteria which address diseases more common in populated areas”, I wonder? Additionally, influenza and chickenpox are viral, so bacterial factors may have limited influence, maybe?
My take away from the article was a bit broader, I think, than just bacterial effects. In the article, the author reports that his review discovered 21 possible pathways through which contact with nature might improve health – these included; natural sights, natural sounds, biodiversity, reduced air pollution, relaxation, physical exercises, improved sleep, social ties, relaxation, awe and so on. Bacterial exposure was not really raised at all and the notion of “altering habitats, or ‘greening-up’, is the way to encourage a greater variety of bacterial protection in the ‘populated areas’ demographic” was not proposed at all, as far as I can see.
I don’t see the link between increasing contact with nature and Genetic Modification – I think this might be more than a bit far fetched to suggest. You suggest that “There is always a risk that exposure to new environmental influences can render previous default protections redundant” is there any evidence for this? Another approach might be to suggest that one of the strengths of our adaptive immune system is to, well, adapt – adapt to new environments and new pathogens. Plus, the immune system is much more than a defence against bacteria or other pathogens – a modern understanding of the immune (neuroimmune) system sees it playing a vital role in neural function including cognition and memory, behaviour and, of course, pain.
The author, far from proposing any kind of genetic modification or increasing bacterial variety suggests instead
“the findings here can help guide the creation of healthy human habitats. The existing literature speaks to the value not only of “wild” nature but also “everyday” nature – the views and green spaces where we live. That physical activity is not consistently related to greener environments suggests that our conceptualization of health-promoting greenspaces should center at least as much on oases as on ball fields, and on greenspaces for walking and quiet contemplation as much as on recreation areas. The findings here suggest that such oases should incorporate plants — especially trees, soil, and water (preferably moving) — and should be designed to induce feelings of deep relaxation, awe, and vitality. Providing these green oases, especially in areas where health risks are high and landscaping is sparse, might be an inexpensive, powerful public health intervention and address persisting health inequalities.”
The paper is in no way suggesting that contact with nature is any kind of panacea (and neither am I), but in my mind, there are many powerful SIMs in everything the author has suggested here, and I can see no downside to encouraging healthy activity in awe inspiring, tree filled, green, clean-air, outdoor environments.
Just briefly, the study on Amazonian tribes was discussed in a BBC4 radio science report…I’ll have to find a link, and post anon. Other opinions expressed are speculative only. In essence, I agree that changing behaviour and environmental exposure might have a beneficial effect on some immune issues. But I tend towards taking the proposition to its extreme limits as a means of evaluating usefulness. Even evaluating controlled graded exposure to greener environments is speculative at this stage, without knowing long term effects…it’s a relatively new proposition. Medications, and their influence, are obviously a huge factor in any assessment of immune deficiencies which might need addressing in the suggested manner.
All healing is ‘conducted’ by the immune system, and subsequently, all peripheral experiences such as pain, quality of life, etc, are affected by the efficacy of those immune responses. That ‘Amazonian’ study also suggested that our varied bacterial status (soup) is the raw material from which our immune systems draws it’s potency….the bacteria must exist before the immune system can employ them. So, as I see it, inevitably, all reactions to any threat, from beginning to end, are evolved from what the immune system has at its disposal at any given time….i.e. the bacterial soup contained within each individual. So, although it might be a good thing to externally influence that source for the immune system for some threats, we also need to be aware of any impact on immune responses which we currently enjoy. With allergies and auto-immune diseases seemingly on the increase, and the possible implication of anti-biotics in that, it’s not too difficult to see that any interference can be a double-edged sword.
I wouldn’t want to confuse my point with any suggestion of general lifestyle improvements not being beneficial for healing purposes….just commenting on the immune system’s involvement in that.
Will try and find ‘Amazon’ link, and post.
Couldn’t find link to radio show. Here’s a link to other BBC published article http://linkis.com/93TLs
Hey Tim, thanks for this. Just a thought but what about the healing effects in architecture? I’m reminded of Esther Sternberg’s (a key player in the advent of psychoneuroimmunology as a hardcore science) book ‘Healing Spaces’. As a personal reflection, being inside buildings like Frank Gehry’s Guggenheim Museum in Bilbao is a magical experience!!
Beautiful example of SIMs being everywhere 😉
I’ve long enjoyed the writing and work of Alain de Botton, and his book/series (The Perfect Home) “The Architecture of Happiness” is just brilliant. In one of those funny things you remember, I recall Alain talking about the concrete of his childhood home in Switzerland- it was poured into forms made from wooden slats, which left the imprint of the wood on the finished surface, along with the imperfections of the gaps between the slats. Even though it was concrete there was still some life and interest in it – a vast contrast to the perfectly flat, lifeless surfaces of the ever growing number of ’til slab’ edifices going up, at least where I live.
We’ve recently had our very first Gehry designed building constructed in Australia – the Dr Chau Chak Wing Building at the University of Technology, Sydney. Like many of Gehry’s designs, it was somewhat polarising, but I think it is quite magnificent and I look forward to visiting in the future.
There was a documentary on it’s construction that aired just a few weeks ago, and while the details of the design and its construction challenges fascinated me, it was the human reactions that really stood out – in particular the interviews with the brickies laying the estimated 320,000 custom designed bricks. Some of these guys had been laying bricks for 20 years, but the common theme was “I’ve never felt like this about a job before – i get up in the morning and can’t wait to go to work and start laying bricks!” One guy had some ink work done on his arm representing the unique brick work and was very proud to show Frank Gehry at the opening of the building.
There’s some lovely links between the writings of Esther Sternberg and notions of embodied cognition, enactivism and extended mind theories, too, I think.
Thanks for dropping by.