Gut Health and Pain – Part 4: Changing your Gut Health

Over the past decade there has been a lot of discussion about the importance of our gut.  Our gut has been shown to be one of the keys to our overall health and wellbeing.

  • It has been called our “second brain” due to the intricate nervous system (the enteric nervous system) it holds within in and how it communicates with our brain (the gut-brain axis).
  • It has been shown to play a vital role in the production of serotonin, which has been one of the keys to understanding the role it plays in mood and sleep.
  • It has been shown to play a vital role in our stress (hypothalamic pituitary adrenal (HPA) axis) and relaxation (through the vagus nerve) response.
  • It is home to 100 trillion microorganisms and their genetic material, known as microbiome, and scientists are only just unlocking the potential of this live bacteria.
  • Some of the most interesting areas being explored by scientists include the role our gut plays in immunity, inflammation and pain.


The following series “Gut Health and Pain” will take a look at the intricate world of our gut and unravel the mystery of why there is thousands journal articles being written each year about the health of our gut and the problems an unhealthy gut can cause.  Welcome to Part 4 – Changing your Gut Health.



Part 4 – Changing your Gut Health

In our last article we discussed the link between how our stress affects our gut and the role relaxation plays in reversing this.  In this final article in our series we will discuss:

  1. Why is our gut health important?
  2. How does our diet impact on our gut bacteria?
  3. What is fibre and why is it important for gut health?
  4. What are prebiotics and how do they impact on gut health?
  5. What are probiotics and how do they impact on gut health?
  6. What dietary changes can you make to improve your gut health?
  7. What other lifestyle changes can you make to improve your gut health?


Why is our gut health important?

There are trillions of bacteria living inside our gut.  Scientist estimate that we have over 10,000 microbial species living within us.  Many of us have heard about the bacteria strains lactobacilli and bifidobacterium, but there are many more than these living within us and each of us has our own unique bacterial footprint.  What is interesting about this bacterial footprint is that researchers are just starting to find the correlation between groups of people with similar gut bacteria types and the diseases they are prone too.  A study released in 2019 highlighted the correlation between fibromyalgia and altered gut bacteria, which opens many possibilities into the treatment for this chronic painful condition.  This asks an interesting question, could changing your gut bacteria through diet, change your risk of certain diseases?


How does our diet impact on our gut bacteria?

For over 15 million years, humans have co-evolved with the gut bacteria which lies within their large intestine.  This gut bacteria: digests the parts of our diet which we are unable to break down on our own (predominantly fibre); it assists us to create vitamins, neurotransmitters and hormones; it trains our immune system and guards it against unwanted pathogens; and it assists with the growth of cells within our gut.


But with the multitude of changes to our lifestyle in the last 200 years, we have also seen changes to our health and gut bacteria.  Studies looking at the Hazda people who still live as hunter-gathers, have shown how a seasonal diet of meat, berries, tubers, baobab (a fruit) and honey, changes their gut bacteria within hours of the meal they digest.  The Hazda people have shown a constantly changing and evolving bacterial landscape, which moves with their diet.  They have also shown higher levels of bacterial richness and diversity, which scientists believe would have been similar to the people living 15 million years ago.  This gut microbiome is believed to contribute their health, well-being and longevity.

Some interesting questions being asked by researchers include: How does our diet have such a dramatic influence on our gut bacteria? Why is it so hard to change our diets?

Our gut bacteria share the food we eat, and they each have their own appetites: yeast eat sugar, Bacteroidetes crave fat, Prevotella enjoy carbs and Bifidobacteria love fibre.  When they are unable to have their appetite met, they can either produce toxins which make us feel less than our best, resulting in headaches, stomach aches or irritability, or increase our cravings for their food source.  This means your diet can either make your gut bacteria flourish and multiply when you feed it the right food, or starve and die.  It also explains why it can take a while to change your diet and the cravings associated with those changes.  But changing your diet is worth it because it leads  to changes in your gut bacteria, gut health and could potentially reduce your risk of certain diseases.

Interesting, when it comes to diet and our gut bacteria, there is no one-size-fits-all approach.  A study completed in 2019 by two researches in Israel highlighted how differently 2 people can respond to the same meal, and how this potentially comes down to how quickly their gut bacteria breaks down the food they eat and allows them to absorb it.  This once again highlighted how unique our gut bacteria is, much like a fingerprint, and also how a personalised diet may assist us on our journey to better gut health.  So, what dietary changes should you make to improve your gut health?



What is fibre and why is it important for gut health?

Fibre is an essential part of diet which is derived from parts of plants which cannot be absorbed or digested by our body.  Fibre assists with our digestion and moving of waste products through our digestive tract.  Fibre moves through our digestive tract to the large intestine where it is broken down by our gut bacteria.  There are different types of fibre which works in different ways within out gut:

  • Soluble fibre: which can be dissolved in water and encourage the growth of our gut bacteria in the large intestine.  This type of fibre has been shown to assist with reducing blood cholesterol levels, lowering fat absorption, helping weight management, stabilising our blood sugar levels and reducing the risk of cardiovascular disease.  Some good sources of soluble fibre include: citrus fruits, oats, beans, peas, oats, barley and apples.
  • Insoluble fibre:  This type of fibre moves through the large intestine intact, and helps to bulk our stools and prevent constipation.  This types of fibre has been shown to help prevent gastrointestinal blockages and lower the risk of diverticular diseases and some cancers.  Some good sources of insoluble fibre include: bran, whole wheat, green beans, cauliflower, nuts, potatoes and beans.
  • Resistant starch: Although not a fibre per se, it acts much like insoluble fibre in our gut, moving through to our large intestine where it helps to build our gut bacteria.  Some good sources of resistant starch include: ‘al centre’ pasta, raw oats, under-ripe bananas and cooked then cooled potatoes.


Fibre is vital for gut health because of the role it plays in preventing many gut-related issues including constipation, irritable bowel syndrome, diverticular disease, haemorrhoids and bowel cancer.  Fibre also acts as a source of food to our gut bacteria, and transportation to assist with the removal of waste products from our digestive tract.


According to the Nutrition Australia, women should be eating 25g of fibre a day and men should be eating 30g of fibre a day.



What are prebiotics and how do they impact on gut health?

In 1995 scientists defined a prebiotic as a “non-digestible food ingredient that beneficially affects the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon”.  In short this means, prebiotics are the food we eat that feed our gut bacteria; the greater the variety of foods, the greater the variety of gut bacteria.

Prebiotics are fibre-rich foods that keep our gut healthy by breaking it down into short chain fatty acids.  SCFA’s are responsible for keeping the lining of our gut healthy: reducing inflammation, increasing nutrient absorption, improving immunity, protecting against bowel cancer and improving mood.  Some good sources of prebiotics include: whole grains, Jerusalem artichokes, legumes and beans, vegetables (particularly green leafy vegetables) and fruit.


Research in this field suggests that diet plays a crucial role in the number and variety of our gut bacteria, it also may play a vital role in the prevention of many diseases.


What are probiotics and how do they impact on gut health?

Probiotics are live micro-organisms which support our gut bacteria and assist in keeping our gut healthy.  Probiotics can be found in a variety of foods, products (such as skin creams), medications, supplements and infant formulas.  Probiotics have been shown to assist with a healthy immune system, improving digestion, producing vitamins, assisting in nutrient absorption and keeping “bad” bacteria at bay.  Researchers have shown that probiotics can be of benefit for people who have diarrhoea or fungal infections after antibiotic use, mild to moderate irritable bowel syndrome, poor digestion of lactose, infection diarrhoea, common infections of the gut, vagina or respiratory tract.


Some good sources of probiotics in foods include: yoghurt, kefir (a fermented probiotic milk drink), sauerkraut, tempeh (a fermented soybean product), kimchi (a fermented, spicy Korean dish), miso (a fermented soybean product), kombucha (a fermented black or green tea), gherkins (a pickled cucumber), natty (a fermented soybean product), and some cheese products (mozzarella, gouda, cheddar and cottage).




What dietary changes can you make to improve your gut health?

As we have discussed in our 3 previous articles (Part 1: Know your Gut, Part 2: The Gut-Brain Connection, Part 3: Your Gut and Stress), our gut bacteria is unique to us, which means there is no one-size fits all solution.  When it comes to us and our gut health, it can sometimes be a game of trial and error.  What we do know for sure: variety in our diet leads to variety in our gut bacteria.


Here is our guide to improving your gut health:

  1. Eat the rainbow in fruit and vegetables: not only are they filled with vitamins and nutrients, they also contain high levels of fibre which stimulate the growth of our good gut bacteria (learn more about the research here)
  2. Try new foods: eating a wide range of foods, helps to promote a wide range of gut bacteria, which appears to lead to better all-round health (learn more about the research here)
  3. Increase your fibre: as we stated above, increasing our fibre promotes gut health, the growth of good gut bacteria and prevention of some diet-related diseases (learn more about the research here)
  4. Introduce fermented foods into your diet: as we mentioned above, fermented food are prebiotics which support good gut bacteria and gut health (learn more about the research here)
  5. Increase resistant starch in your diet: this acts like insoluble fibre, moving to the large intestine and promoting the growth of our good gut bacteria (learn more about the research here)
  6. Eat more whole grains: whole grains are high in fibre and contain many non-digestible carbohydrates which are broken down in the large intestine and promote the growth of different gut bacteria.  Eating whole grains can keep us full for longer, reduce the risk of heart disease and inflammation (learn more about the research here).  Whole grains also produce short-chain fatty acids (SCFAs) which are responsible for provision energy to our intestinal cells and our body.  They are responsible for maintaining the integrity of the gastrointestinal tract, which is important for reducing the risk of infections or inflammation (learn more here)
  7. Change your plate ratios: increase the levels of vegetables, legumes, seeds, nuts and fruits on your plate.  People who eat a higher proportion of plant-based foods, tend to have lower risks of obesity, inflammation and cholesterol (learn more about the research here).  The Mediterranean diet has been shown to have the right combination of plant-based foods, polyphenols, lean meat, good fats and oily fish for improving gut health (learn more here).
  8. Increase your intake of foods high in polyphenols:  these are a micronutrient found in plants which are often digested in the gut by our gut bacteria.  They are the most abundant antioxidant in our body, they pair up with free radicals and play a role in protecting us from chronic illness.  This is partly why they have been linked to reducing inflammation, blood pressure, cholesterol and oxidative stress.  Polyphenols play a role in the growth of  good bacteria, which break down fibre and convert it into vitamins and short chain fatty acids.   They have also been associated with Akkermansia muciniphila, which accounts for up to 4% of your intestinal bacteria and is associated with lean body mass and obesity prevention.  Some high polyphenol foods include: dark chocolate, grape skins, green tea, almonds, red wine, blueberries, broccoli and onions (learn more about the research here)


What other lifestyle changes can you make to improve your gut health?

Our gut bacteria and health doesn’t solely lie in the hands of our diet.  Beneath we will discuss each of the other lifestyle factors which play a role in our gut bacteria, health and wellbeing:

  • Managing our stress:  As we discussed in Part 3 – Your Gut and Stress, our stress levels play a large role in the health of our gut and its lining, our metabolism and weight and even our pain.  Managing our stress levels helps to alleviate the toll this takes on us, to learn more about stress management techniques visit here.
  • Good quality sleep: Another factor we discussed in Part 2 – The Gut-Brain Connection, is our sleep and the role it plays on our gut bacteria, the hormones we produce which manage appetite and hunger.  To learn more about improving our sleep visit here.
  • Moving more:  Exercise has been shown to change the diversity and functional capacity of our gut bacteria, and our health and wellbeing.  Studies have shown that exercise increases in the number of beneficial microbial species and enhances short-chain fatty acid production and carbohydrate metabolism.  Studies have shown how increasing the level of exercise leads to a greater diversity in Firmicutes (involved in fermentation), an increase of F. prausnitzii and Roseburia hominis, associated with fueling cells of the gut lining, helping maintain its integrity and reducing inflammation, and an increase of Akkermansia muciniphila associated with metabolism and healthy weight.  Moving more also has positive effects on our mood, pain and sleep.  To learn more about moving more visit here.


    A final note, remember when it comes to gut health it is always important to speak with your doctor to clear any underlying issues such as:


    Additional references

    • Journal Article:  Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms (link here)
    • Journal Article: Effects of Diet on Gut Microbiota Profile and the Implications for Health and Disease (link here)
    • Journal Article:  The gut microbiome: Relationships with disease and opportunities for therapy (link here)
    • Article:  Hunter-gatherers’ seasonal gut-microbe diversity loss echoes our permanent one (link here)
    • Journal Article:  Fiber-Mediated Nourishment of Gut Microbiota Protects against Diet-Induced Obesity by Restoring IL-22-Mediated Colonic Health (link here)
    • Journal Article:  The hot air and cold facts of dietary fibre (link here)
    • Journal Article:  Commensal bacteria and essential amino acids control food choice behavior and reproduction (link here)
    • Journal Article:  Eubiosis and dysbiosis: the two sides of the microbiota (article here)
    • Article:  Our gut microbiome is always changing; it’s also remarkably stable (link here)
    • Book: Gut Health and Probiotics.  The science behind the hype. Jenny Tschiesche
    • Book: Rushing Woman’s Syndrome.  The impact of a never ending to-do list on your health.  Dr Libby Weaver
    • Book: Gut.  The inside story of our body’s most under-rated organ. Giulia Enders
    • Book: The mind-gut connection.  How the hidden conversation within our bodies impacts on our mood, our choices, and our overall health.  Emeran Mayer, MD
    • Journal Article: The role of gut microbiota in immune homeostasis and autoimmunity (article here)
    • Journal Article: The Role of Gut Microbiota in Intestinal Inflammation with Respect to Diet and Extrinsic Stressors (article here)
    • Journal Article: Gut microbiota functions: metabolism of nutrients and other food components (article here)
    • Journal Article: Stress and the gut microbiota-brain axis (article here)
    • Journal Article: The gut microbiome: Relationships with disease and opportunities for therapy (article here)
    • Journal Article: Neurotransmitter modulation by the gut microbiota (article here)
    • Journal Article:  Human nutrition, the gut microbiome and the immune system (article here)
    • Journal Article:  The microbiome: A key regulator of stress and neuroinflammation (article here)
    • Journal Article:  Current Understanding of Gut Microbiota in Mood Disorders: An Update of Human Studies (article here)
    • Journal Article:  Role of gut microbiota in brain function and stress-related pathology (article here)
    • Journal Article:  Intestinal permeability – a new target for disease prevention and therapy (article here)
    • AUSMED E-Learning: Gut Microbiota Health and Wellbeing (link here)
    • Journal Article: A review of lifestyle factors that contribute to important pathways associated with major depression: Diet, sleep and exercise (article here)
    • Journal Article:  ‘Gut health’: a new objective in medicine? (article here)
    • Journal Article:  Impact of the gut microbiota on inflammation, obesity, and metabolic disease (article here)
    • Journal Article:  The Gut Microbiome as a Major Regulator of the Gut-Skin Axis (link here)
    • Journal Article:  Dietary Modulation of the Human Colonic Microbiota: Introducing the Concept of Prebiotics (link here)
    • Journal Article:  Prebiotics: why definitions matter (link here)
    • Journal Article:  Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics (link here)
    • Article:  ISAPP: Prebiotics (link here)
    • Journal Article: Clinical uses of probiotics (link here)
    • Journal Article:  Six-week Consumption of a Wild Blueberry Powder Drink Increases Bifidobacteria in the Human Gut (link here)
    • Journal Article:  Effects of Almond and Pistachio Consumption on Gut Microbiota Composition in a Randomised Cross-Over Human Feeding Study (link here)
    • Journal Article:  Impact of Increasing Fruit and Vegetables and Flavonoid Intake on the Human Gut Microbiota (link here)
    • Journal Article:  Effect of Apple Intake on Fecal Microbiota and Metabolites in Humans (link here)
    • Journal Article:  Prebiotic Effect of Fruit and Vegetable Shots Containing Jerusalem Artichoke Inulin: A Human Intervention Study (link here)
    • Journal Article:  Dietary effects on human gut microbiome diversity (link here)


    Images courtesy of Unsplash and iStock
    Written by Aimee Carter