Welcome to my blog post ‘Learn About The Dirty Little Secret Of Poor Gut Health: Air Pollution’.
You may also be interested in these other blog posts:
- The Ultimate Guide To Irritable Bowel Syndrome: click here.
- Can gut health and our microbiome effect mental health?: click here.
- Irritable Bowel Syndrome & Chronic Fatigue Syndrome: click here.
What Is The Dirty Little Secret Of Poor Gut Health?
Work has shown that increased exposure to air pollutants independently contributes to obesity and type 2 diabetes risk, and while the exact mechanisms underlying these associations are not fully understood, recent research (1) discusses the findings regarding the impact of inhaled and ingested air pollutants on the gut microbiome.
Animal and human studies provide evidence that air pollutants, such as particulate matter, nitrogen oxides, and ozone, have the potential to alter the gut microbiome. Further, studies suggest that such exposure-induced alterations to the gut microbiome may contribute to increased risk for obesity and type 2 diabetes through inflammatory pathways.
Therefore, exposure to air pollutants may contribute to increased risk for obesity and type 2 diabetes through alterations to gut microbial composition and function.
For example, several studies have found associations between elevated levels of air pollution exposure and gastrointestinal diseases, including inflammatory bowel disease (IBD), irritable bowel syndrome, appendicitis, and gastroenteric disorders in infants. Cigarette smoke, which contains particulates that are present in ambient and traffic-related air pollution, has also been shown to alter the composition of the gut microbiota.
Studies have provided preliminary evidence that exposure to airborne particles may alter the gut microbiota and gut health
How Does Air Pollution Affect The Digestive System?
It has been proposed that air pollution can affect the digestive system due to:
- The pro- and anti-bacterial effects of particle matter such as black carbon and toxic metals such as lead.
- Biofilm formation.
- Ozone induced activation of the HPA axis.
The GI tract is exposed to large amounts of particle matter, which has the potential to exert pro- and anti-bacterial effects on gut bacteria that may alter gut physiology, including immune responses, metabolism, and intestinal permeability (aka leaky gut).
For example, studies suggest that components of air pollution, such as elemental carbon, black carbon, nitrates, sulfates, and toxic metals like lead and arsenic may alter host bacterial communities through antimicrobial properties and the formation of biofilms.
Ozone induced activation of the HPA axis may increase the production of cortisol and norepinephrine, which may alter the composition of the gut microbiota.
Stress hormones such as noradrenaline may also induce changes in the enteric nervous system, which can alter gastrointestinal motility, mucus secretion, and ion transport. Such changes in the gut environment could lead to alterations in the gut microbiome.
Overall, this hypothesised mechanism is supported by the gut-brain axis, which allows for bidirectional communication that may result in changes in bacterial proliferation in the presence of noradrenaline at the gut.
It is suggested that the requirement for microbial input from the environment to drive immunoregulation is a major component of the beneficial effect of green space, and a neglected ecosystem service that is essential for our well-being (11).
Summary for ‘Learn About The Dirty Little Secret Of Poor Gut Health: Air Pollution’:
So this is the dirty little secret of gut health!
- Exposure to air pollutants is associated with the composition of the gut microbiome.
- Ozone exposure is associated with lower gut microbial diversity, higher levels of the bacteria ‘bacteroides caecimuris’, and multiple gene pathways.
- Air pollution may contribute to alterations in the composition and function of the human gut microbiome.
References For ‘Learn About The Dirty Little Secret Of Poor Gut Health: Air Pollution’
- Exposure to air pollutants and the gut microbiota: a potential link between exposure, obesity, and type 2 diabetes: click here.
- Air pollution exposure is associated with the gut microbiome as revealed by shotgun metagenomic sequencing: click here.
- Exposure to Traffic-Related Air Pollution and the Composition of the Gut Microbiota in Overweight and Obese Adolescents: click here.
- Air Microbiome and Pollution: Composition and Potential Effects on Human Health, Including SARS Coronavirus Infection: click here.
- Longitudinal survey of microbiome associated with particulate matter in a megacity: click here.
- Air Pollution, Early Life Microbiome, and Development: click here.
- Environmental triggers in IBD: a review of progress and evidence: click here.
- Gut Dysbiosis in Animals Due to Environmental Chemical Exposures: click here.
- Impact of air quality on the gastrointestinal microbiome: A review: click here.
- Air pollution: An environmental factor contributing to intestinal disease: click here.
- Regulation of the immune system by biodiversity from the natural environment: an ecosystem service essential to health: click here
- Role of environmental pollution in irritable bowel syndrome: click here.
- Contribution of Non-immune Cells to Activation and Modulation of the Intestinal Inflammation: click here.