Understanding the gut microbiome and gut health
We have a tiny ecosystem inside of us. This ecosystem spans from our mouth to our stomach and through our intestines, all the way to the other end. This ecosystem is diverse, it has trillions of inhabitants called microbiota. This entire ecosystem and its environment inside of us is our gut microbiome.
Microbiota are the bacteria, pathogens and other tiny microorganisms colonising our gastrointestinal tract. Microbiota diversity and the level of harmony in which they live correlates with the health of our gut microbiome.
As individuals, we have a microbial ‘fingerprint’ that is unique to us and us alone. However, it is not static: it develops and fluctuates due to progressive life stages and various lifestyle practices, which can affect it both positively and negatively through normal fluctuations.
The impact of gut health on your overall wellbeing
Much like a rainforest, the diversity of your unique microbiota directly correlates with the health of this ecosystem (the gut microbiome).
A persistent imbalance of our gut microbiota is generally referred to as dysbiosis1. Depending on the relative species, in some severe circumstances dysbiosis has been linked to multiple adverse health effects in medically diagnosed conditions such as Inflammatory Bowel Disease (IBD), Irritable Bowel Syndrome (IBS), mental health illnesses, eczema, type 2 diabetes, cancer and obesity1,2,3.
What causes dysbiosis?
Poor diet quality, ‘yo-yo dieting’, certain medications, smoking, illness, minimal exercise, environmental toxins, stress and the use of antibiotics are just some of the lifestyle factors that can compromise your gut microbiome leading to dysbiosis. Luckily, many of factors contributing to dysbiosis are modifiable.
Inappropriate use of antibiotics
Antibiotics are generally used to combat pathogenic bacteria within a host. Antibiotic use can form part of essential medical treatment that may be lifesaving.
Unfortunately, a course of broad-spectrum antibiotics has been shown in research to wipe out beneficial bacteria as well as the pathogens the antibiotics are targeting. This may result in dysbiosis and a subsequent decrease in microbiota diversity, where reports have shown repopulation of some species can take up to four years post antibiotic treatment4.
This is not to say avoid antibiotics altogether, but you may think twice if you regularly jump on antibiotics for the common cold. It is up to you to discuss with your medical doctor about what is appropriate use (and frequency of use) of antibiotics for your health in the long-term.
How can we support a healthy gut microbiome?
We can take small steps to improve our gut health and encourage a thriving gut microbiome. Did you know, microbial composition can be altered by changing our diet with positive results seen as early as 24 hours?!
The Food and Mood Centre regularly reviews the scientific evidence and have concluded that having lots of different, diverse types of bacteria living in our gut is a good thing. Such diversity can allow your gut microbiome to be in a better position to fight off and resist pathogens5.
Rather than focusing on a specific strain or amount of ‘good bacteria’, an easier option, as recommended by The Food and Mood Centre, is to focus on broader researched-backed behaviours that promote a well-functioning gut microbiome. This includes eating a healthy and plant-based diet, regularly exercising, having adequate sleep, and reducing your exposure to stress.5
Dietary strategies for Microbiome Diversity
Latest research is pointing to the consumption of whole foods that contain dietary fibre, prebiotics and polyphenols for improved gut microbiome health.
The Facts on Fibre
Dietary fibre is a nutrient found in plant foods that is indigestible when we eat it. There are three main types of fibre:
- soluble fibre
- insoluble fibre
- resistant starch
Each play a different role in the body but all are essential and beneficial for digestive health as well as a disease prevention strategy6.
Soluble fibre assists in slowing the emptying process in our stomachs, helping you to feel fuller. It also helps to lower cholesterol and stabilise blood glucose levels6. Soluble fibre is found in fruits, vegetables, oats, barley and legumes.
When insoluble fibre is consumed it absorbs water to help to soften the contents of our bowels and support regular bowel movements. It also helps to keep us full and keep the bowel environment healthy6. This type of fibre is found in wholegrain breads and cereals, nuts, seeds, wheat bran and the skin of fruit and vegetables.
Resistant starch is the third type of fibre which travels to the large intestine and acts as a food for our beneficial bacteria, having a prebiotic effect7. Resistant starch comes from green bananas, whole grains, legumes, beans and starchy vegetables like sweet potato and corn.
Probiotics Vs. Prebiotics
When it comes to optimising gut health, probiotics seem to be centre stage. However, prebiotics are equally as important. So, what is the difference?
Probiotics
Probiotics are living ‘good’ bacteria. They are classified in order of Genus > Species > Strain. For example, Lactobacillus rhamnosus GG or Lactobacillus (genus), rhamnosus (species) GG (strain). Specific strains at defined doses have been identified to support specific areas in health and disease8. However, if there is research backing one particular strain, this does not mean the entire probiotic species will have the same result, only that specific strain. It’s common practice for supplement manufacturers to extrapolate research results to the strain they are selling. This simply is incorrect and supplementing with that product will likely have nil effect.
The International Scientific Association for Probiotics and Prebiotics (ISAPP) is an international non-profit organisation that at the forefront of probiotic and prebiotic science. ISAPP has collated current evidence and determined that specific probiotic strains at the right dose can:
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Reduce antibiotic-associated diarrhoea
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Treat infectious diarrhoea
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Improve mild to moderate irritable bowel syndrome (IBS) and other digestive issues
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Help manage symptoms associated with poor digestion of lactose
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Reduce colic symptoms and reduce risk of eczema in infants
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Decrease some common infections, including those of the respiratory tract, gut, and vaginal tract9
A specific health benefit is entirely dependent on the strain and dosage. A common misconception about probiotic supplements is that a multi-strain product with the highest count means it is a better and more effective product - this is not necessarily true.
There are a wide variety of probiotic strains available for purchase. Most commercial probiotics are strains from Bifidobacterium, Lactobacillus, and Saccharomyces. It’s common practice that product manufacturers make beneficial health claims about their product despite having the wrong strain and dosage.
It’s important to remember when choosing a probiotic supplement that the product contains the specific strain and at the correct dosage that aligns with your desired health benefit.
Prebiotics
Prebiotics, on the other hand, are not live. They are typically natural substances found in food that, in general terms, act as a food source for our good bacteria.
The definition of a prebiotic has been modified to 'a substrate that is selectively utilised by host microorganisms conferring a health benefit'10. With this broad concept in mind, we may see many more substances popping up in our food system that are classified as a prebiotic.
Prebiotic food examples include:
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Fructooligosaccharides (FOS) and inulin from chicory root, dandelion, artichoke, asparagus, agave, garlic, onion and leeks
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Galactooligosaccharides (GOS) from dairy and legumes
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Resistant starch from green banana, whole grains, legumes, beans and starchy vegetables like sweet potato and corn
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Beta-glucan from oats and barley
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Pectin from apples
The consumption of prebiotics has been associated with growth of Bifidobacterium, Lactobacillus and lactic acid bacteria, as well as other health benefits.10
Unlike probiotics, prebiotics can resist gastric acid and enzyme breakdown so they reach the colon where they can be metabolised by our gut microbiota to produce short-chain fatty acids (SCFAs)10
Supplementing prebiotics in your diet can influence your gut microbiota composition as well as the production of SCFA. These two factors will have a positive effect on gut health overall.
Polyphenols
Polyphenols are natural and beneficial compounds commonly found in plant foods and some beverages such as fruit, vegetables, cereal grains, tea, coffee, dark chocolate, cocoa and wine.
There are a class of plant polyphenols that can also meet the criteria of prebiotics. Approximately 90–95% of dietary polyphenols are not absorbed in the small intestine and so they reach the colon where they undergo extensive biotransformation by our gut microbiota.11
It’s under these circumstances that they become bioactive substances suggested to have anti-inflammatory and antioxidant properties as well as becoming protective against pathogenic microbes that enter our gut.12
Incorporating a diverse variety of colourful vegetables and fruit into your diet is a simple strategy to up your polyphenol intake.
The Impact of Artificial Sweetners
With improving processing technology and health movements in attempt to avoid sugar, artificial sweeteners are found in abundance in everyday foods on our supermarket shelves.
Some studies have indicated that when consumed, non-caloric artificial sweeteners can alter microbial pathways which have been linked to changes in our susceptibility to metabolic disease.13
Unlike other low-calorie sweeteners, steviol glycosides (extracted from stevia leaf) is natural. To date, there is no evidence that steviol glycosides adversely impact bacteria in our colon.13
If you are concerned about artificial sweeteners in your diet, simply check the ingredients list usually located on the back of food packaging or contact the manufacturer directly.
Monash University and the development of True Gut Health
Recently, our friends from the Department of Nutrition, Dietetics & Food at Monash University, Victoria conducted a systematic review of literature to determine the beneficial or detrimental effect of different pre-, pro- and synbiotics, taken by active adults, on gastrointestinal outcomes at rest and in response to exercise.
What does this mean? They searched through all the relevant scientific studies to date which were conducted on active adults who supplemented their diet with ‘gut health’ products, and they summarised the results.
Long story short: the findings and recommendations of the systematic review conducted by the team at Monash in 2020 has shaped the purpose-built formulation that is True Gut Health.
True Gut Health
True Gut Health is a scientifically formulated blend of naturally derived ingredients to support microbiome diversity and nurture a healthy feeling gut. This purpose-built formulation contains a mix of dietary fibre, prebiotics, collagen and seaweed and plant extracts.
True Gut Health contains several prebiotics including organic inulin from the blue agave plant, Sunfiber®, a form of soluble fibre derived from the guar plant which is native to West India, and Galactooligosaccharide or ‘GOS’ from whole milk.
True Gut Health is sweetened with naturally derived monk fruit extract and contains nothing artificial. No artificial colours, no artificial preservative, no artificial additives - full stop. It is gluten, peanut, tree nut and soy free, as well as free from genetically modified ingredients or palm oil. See the full list of ingredients below.
Ingredients: Hydrolysed collagen peptides, Galactooligosaccharide (GOS), Sweet potato powder, Sunfiber®, Coconut water powder, Organic inulin, Green banana flour, Natural coconut flavours, Organic Ceylon cinnamon, Fucus vesiculosus extract (Tasmanian seaweed), Xanthan gum, Pomanox®️ pomegranate extract P30, Apple peel extract, Acai berry extract, Monk fruit extract, Ground ginger.
Key Messages:
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There is an entire ecosystem thriving inside of our gastrointestinal tract. This is our gut microbiome.
-
Our gut microbiome is not static. It changes and develops during progressive life stages and can be altered with various lifestyle practices.
-
Improving gut microbial diversity can allow your microbiome to be in a better position to fight off and resist pathogens.
-
Changing our diet can alter our gut microbiome where positive results can be seen as quickly as 24 hours later!
-
Dietary fibre is an indigestible component of plant foods that is essential for good health. Soluble fibre, insoluble fibre and resistant starch are the three main types of dietary fibre, all of which are beneficial to include in the food we choose to eat.
-
Probiotics are live ‘good’ bacteria. Specific strains at defined doses have been identified to support specific areas in health and diseases.
-
Prebiotics are typically natural substances found in food that, in general terms, act as a food source for our good bacteria.
-
Incorporating a diverse variety of colourful vegetables and fruit into your diet is a simple strategy to up your polyphenol intake.
-
If you are concerned about artificial sweeteners in your diet, simply check the ingredients list usually located on the back of food packaging
-
True Gut Health is a scientifically formulated blend of naturally derived ingredients to support a healthy microbiome diversity and nurture a healthy feeling gut.
-
True Gut Health is purpose built from the research and recommendations from the team at the Department of Nutrition, Dietetics & Food at Monash University, Victoria, Australia.
References
- Belizário JE, Faintuch J. Microbiome and Gut Dysbiosis. Exp Suppl. 2018;109:459-476. doi: 10.1007/978-3-319-74932-7_13. PMID: 30535609
- Bull MJ, Plummer NT. Part 1: The Human Gut Microbiome in Health and Disease. Integr Med (Encinitas). 2014;13(6):17-22.
- Clapp M, Aurora N, Herrera L, Bhatia M, Wilen E, Wakefield S. Gut microbiota's effect on mental health: The gut-brain axis. Clin Pract. 2017;7(4):987. Published 2017 Sep 15. doi:10.4081/cp.2017.987
- Ursell LK, Metcalf JL, Parfrey LW, Knight R. Defining the human microbiome. Nutr Rev. 2012;70 Suppl 1(Suppl 1):S38-S44. doi:10.1111/j.1753-4887.2012.00493.x
- https://foodandmoodcentre.com.au/2016/07/what-is-the-gut-microbiome/
- Fibre. Nutrition Australia Vic Division, October 2014. Cited 17/06/2021 online via: https://nutritionaustralia.org/fact-sheets/fibre/
- Dr J.Barrett. 14 November 2016. Dietary fibre series - resistant starch. Cited 17/06/2021 online via: https://www.monashfodmap.com/blog/dietary-fibre-series-resistant-starch/
- Hawrelak, JA. (ed). What are Probiotics? Probiotic Advisor. Illuminate Natural Medicine, 2015. Cited 25/06/2021 online via: https://www.probioticadvisor.com/probiotic-essentials-1/what-are-probiotics/
- International Scientific Association for Probiotics and Prebiotics. 2019. Cited 17/06/2021 online via: https://isappscience.org/
- Leeming ER, Johnson AJ, Spector TD, Le Roy CI. Effect of Diet on the Gut Microbiota: Rethinking Intervention Duration. Nutrients. 2019;11(12):2862. Published 2019 Nov 22. doi:10.3390/nu11122862
- Gibson, G., Hutkins, R., Sanders, M. et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics. Nat Rev Gastroenterol Hepatol 14, 491–502 (2017). https://doi.org/10.1038/nrgastro.2017.75
- Kumar Singh A, Cabral C, Kumar R, et al. Beneficial Effects of Dietary Polyphenols on Gut Microbiota and Strategies to Improve Delivery Efficiency. Nutrients. 2019;11(9):2216. Published 2019 Sep 13. doi:10.3390/nu11092216
- Rinninella, E.; Cintoni, M.; Raoul, P.; Lopetuso, L.R.; Scaldaferri, F.; Pulcini, G.; Miggiano, G.A.D.; Gasbarrini, A.; Mele, M.C. Food Components and Dietary Habits: Keys for a Healthy Gut Microbiota Composition. Nutrients 2019, 11, 2393. https://doi.org/10.3390/nu11102393