A biodiversity hypothesis

Abstract

Biodiversity hypothesis states that contact with natural environments enriches the human microbiome, promotes immune balance and protects from allergy and inflammatory disorders. We are protected by two nested layers of biodiversity, microbiota of the outer layer (soil, natural waters, plants, animals) and inner layer (gut, skin, airways). The latter inhabits our body and is colonized from the outer layer. Explosion of human populations along with cultural evolution is profoundly changing our environment and lifestyle. Adaptive immunoregulatory circuits and dynamic homeostasis are at stake in the newly emerged urban surroundings. In allergy, and chronic inflammatory disorders in general, exploring the determinants of immunotolerance is the key for prevention and more effective treatment. Loss of immunoprotective factors, derived from nature, is a new kind of health risk poorly acknowledged until recently.The paradigm change has been implemented in the Finnish allergy programme (2008-2018), which emphasized tolerance instead of avoidance. The first results are promising, as allergy burden has started to reduce. The rapidly urbanizing world is facing serious biodiversity loss with global warming, which are interconnected.Biodiversity hypothesis of health and disease has societal impact, for example, on city planning, food and energy production and nature conservation. It has also a message for individuals for health and well-being: take nature close, to touch, eat, breathe, experience and enjoy. Biodiverse natural environments are dependent on planetary health, which should be a priority also among health professionals. K E Y W O R D Sasthma, biodiversity, hygiene hypothesis, immune tolerance, microbiome

Health impact of the Anthropocene: the complex relationship between gut microbiota, epigenetics, and human health, using obesity as an example

“…Biodiversity loss is directly impacting the microbiota diversity of humans, soil and other species, which are interrelated [3]. Decreased diversity of the human gut microbiota during the development phase and during later life course can have several impacts on health outcomes [4,5]. One of the pathways of interaction between the human gut microbiota and health outcomes is through epigenetics.…”

Residential neighbourhood greenspace is associated with reduced risk of cardiovascular disease: A prospective cohort study

“…The causes of the association between greenspace exposure and incident CVD remain largely unexplained, despite a growing body of work in this field [30,71]. Other explanatory mechanisms are likely to explain the causal link such as the physiological and psychological benefits of seeing greenspace [72], including stress reduction and restoration [73]; the role of greenspace in creating a sense of attachment to place and community, and reduced isolation [74] and increased social ties [73]; the advantages of exposure to nature for immunological regulation [73,[75][76][77][78][79]; and, albeit with less evidence, the 'biogenics' hypothesis, that natural toxins and compounds can reduce unhealthy cell activity in humans, and reduce the incidence of disease [73]. Residential neighbourhood greenspace and risk of cardiovascular disease: A prospective cohort study…”

Role of viruses in asthma

“…2 [3,14]. Rapid urbanization, pollution, and climate change, all leading to the loss of biodiversity, promote chronic noncommunicable illnesses such as asthma and allergies [42]. Exposure to pollutants such as NO 2 and high exposure to allergens in children with allergic asthma increase the severity of virus-induced exacerbations of asthma.…”