Associated with Gut
Recent research has linked the gut microbiome to a number of health conditions including...
Multiple by-products from gut microbes are linked to cardiovascular disease. An example is the molecule LPS which is released by certain microbes and is known to increase cholesterol deposition in artery walls. 3
Click HERE to read about how your mouth wash could be contributing to cardiovascular disease risk by altering the oral microbiome!
70-80% of the immune system resides in the gut!
The immune system in the gut, which is largely regulated by the microbiome, effects systemic immune responses.
When the microbiome and immune system aren't functioning optimally we see conditions such as pollen and grass allergies, eczema, asthma and food intolerances. 1
The gut microbiome even plays a crucial role in autoimmune conditions! (e.g. rheumatoid arthritis, SLE, Hashimotos, IBD, ankylosing spondylitis)
An imbalanced gut microbiome may provoke autoimmune conditions by dysregulating systemic immune function. Or an impaired gut wall known as 'leaky gut' may allow gut bacteria to cross instigating an autoimmune response. 2
The gut and brain have multiple communication pathways (these include the vagus nerve, immune system and various signaling molecules). This communication is termed the gut-brain axis!
Gut dysbiosis can increase brain inflammation and alter its structure and function. This is implicated in numerous mental health and behavioural disorders including anxiety, depression, bipolar disorder, schizophrenia, ADD and ADHD. 4-6
The gut microbiome can play numerous roles in insomnia. These could include increasing brain inflammation, altering the production and metabolism of neurotransmitters required for sleep, and by impairing the absorption of nutrients required to create these neurotransmitters. 7
To read more click HERE
The gut microbiome plays a role in neuro-degenerative conditions such as Alzheimer's and Parkinson's.
This is largely mediated through the vagus nerve, immune system and various signaling molecules.
The gut microbiome is capable of modulating neurotransmitter levels and can increase risk of cardiometabolic diseases such as diabetes and atherosclerosis which predispose Alzheimer's.
Whilst all neurodegenerative diseases have different pathogenesis, they all feature neuroinflammation which can stem from the gut. Healthy aging has been associated with a diverse gut microbiome. 8
Click HERE to read more about changes to the gut microbiome with aging!
Skin conditions including acne, eczema and psoriasis commonly share a dysbiosis component.
The gut microbiome may influence the skin by interacting with the skin microbiome, the immune system and by influencing blood glucose/insulin levels which can contribute to proliferation of psoriasis lesions and increase acne severity. 9-11
Click HERE to read more about the skin microbiome!
Type 2 diabetes
A healthy gut microbiome produces compounds which help to regulate metabolism, including insulin sensitivity, hunger and satiety levels!
Research suggests that dysbiosis contributes to insulin resistance/elevated blood sugar. 12
Click HERE to read how artificial sweeteners can disrupt the gut microbiome resulting in poor insulin sensitivity.
Gut dysbiosis may contribute to fatty liver by impairing nutrient absorption, creating toxic by-products, releasing inflammatory messengers, and contributing to insulin resistance.
Translocation of bacteria from the gut may also contribute to the progression of liver disease.
Click HERE to read about the role of the gut microbiome in alcohol induced liver dysfunction.
Gastrointestinal symptoms such as diarrhoea, constipation, reflux, bloating and pain are clearly linked to gut microbiome composition.
A great example is irritable bowel syndrome (IBS) which is frequently caused by small intestinal bacterial overgrowth (SIBO) or intestinal methanogen overgrowth (IMO). SIBO is commonly responsible for diarrhoea dominant IBS and IMO frequently a culprit in constipation dominant IBS.
But did you know that dysbiosis can be present in the absence of any gut symptoms?
1. Bull, M. J. & Plummer, N. T. Part 1: The Human Gut Microbiome in Health and Disease. Integr. Med. A Clin. J. 13, 17 (2014).
2. Xu, H. et al. The Dynamic Interplay between the Gut Microbiota and Autoimmune Diseases. J. Immunol. Res. 2019, (2019).
3. González-Sarrías, A. et al. The Endotoxemia Marker Lipopolysaccharide-Binding Protein is Reduced in Overweight-Obese Subjects Consuming
Pomegranate Extract by Modulating the Gut Microbiota: A Randomized Clinical Trial. Mol. Nutr. Food Res. 62, 1–10 (2018).
4. Martin, C. R., Osadchiy, V., Kalani, A. & Mayer, E. A. The Brain-Gut-Microbiome Axis. CMGH vol. 6 133–148 (2018).
5. Yaghoubfar, R. et al. Modulation of serotonin signaling/metabolism by Akkermansia muciniphila and its extracellular vesicles through the gut-
brain axis in mice. Sci. Rep. 10, (2020).
6. Spielman, L. J., Gibson, D. L. & Klegeris, A. Unhealthy gut, unhealthy brain: The role of the intestinal microbiota in neurodegenerative
diseases. Neurochemistry International vol. 120 149–163 (2018).
7. Nayak, B. N., Singh, R. B. & Buttar, H. S. Role of tryptophan in health and disease: Systematic review of the anti-oxidant, anti-inflammation,
and nutritional aspects of tryptophan and its metabolites. World Heart J. 11, 161–178 (2019).
8. Westfall, S. et al. Microbiome, probiotics and neurodegenerative diseases: deciphering the gut brain axis. Cellular and Molecular Life Sciences
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9. Wang, F. Y. & Chi, C. C. Rosacea, Germs, and Bowels: A Review on Gastrointestinal Comorbidities and Gut–Skin Axis of Rosacea. Advances in Therapy 1–10 (2021) doi:10.1007/s12325-021-01624-x.
10. Myers, B. et al. The gut microbiome in psoriasis and psoriatic arthritis. Best Practice and Research: Clinical Rheumatology vol. 33 101494 (2019).
11. Prescott, S. L. et al. The skin microbiome: Impact of modern environments on skin ecology, barrier integrity, and systemic immune
programming. World Allergy Organization Journal vol. 10 (2017).
12. Pascale, A., Marchesi, N., Govoni, S., Coppola, A. & Gazzaruso, C. The role of gut microbiota in obesity, diabetes mellitus, and effect of
metformin: new insights into old diseases. Current Opinion in Pharmacology vol. 49 1–5 (2019).
13. Guohong-Liu, Qingxi-Zhao & Hongyun-Wei. Characteristics of intestinal bacteria with fatty liver diseases and cirrhosis. Annals of Hepatology
vol. 18 796–803 (2019).
14. Leite, G. et al. The duodenal microbiome is altered in small intestinal bacterial overgrowth. PLoS One 15, (2020).
15. Sperber, A. D. et al. Worldwide Prevalence and Burden of Functional Gastrointestinal Disorders, Results of Rome Foundation Global Study.
Gastroenterology 160, 99-114.e3 (2021).