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Gut Dysbiosis and IBS

Are bacteria to blame for your symptoms of IBS?

“Recent findings suggest that IBS is linked to clearly detectable gut microbiota alterations. Thanks to new diagnostic insights and a rapidly growing knowledge about the role and function of the microbial communities living inside our guts, our view on IBS and its causes has changed considerably.”

President of the European Society of Neurogastroenterology and Motility (ESNM) Professor Giovanni Barbara

What is dysbiosis?

Your gut microbiome is a community of different microorganisms, including bacteria, bacteriophages, viruses, archaea, and fungi. This community participates in maintaining intestinal balance through the “training” of the immune system and inhibiting growth of pathogens and pathobionts.

Gut dysbiosis is a condition in which the bacteria in your gut are out of balance, and pathogens and/or pathobionts begin to dominate, creating symptoms of digestive disturbance. There is more and more evidence accumulating that dysbiosis may play a key role in the development of IBS. (1, 2)

You are an ecosystem

We have over 100 trillion microbes living inside our bodies, most of them residing in our colon; these microbes are known as your microbiota.  Your gut is home to a complex ecosystem of 800 different species of microbiota, which include 7,000 different strains. Amazingly, our bodies contain 10 times more bacteria than we have cells!

Some of the most important roles of these microbes are to help to maintain the integrity of the mucosal barrier, pathogen resistance and the production of vitamins and SCFAs. In addition, the interaction between commensal microbiota and the mucosal immune system is crucial for proper immune function.

The composition and balance of our gut microbiota differs a lot among people, but certain bacteria should dominate and act to suppress the overgrowth of harmful or pathogenic bacteria.

The Bad Guys

Although most of the bacteria in our gut are beneficial to us, some bacterial species, such as B.fragilis, C.difficile and Shigella, may colonise the gut and are potentially harmful. (3) These species, referred to as opportunistic bacteria, when in small numbers and under control actually fulfil some important functions in the gut, like assisting in the digestion of food, breaking down fats and bile acids.

In a balanced, healthy gut, the amount of these bacteria is limited and kept under control by the beneficial flora. (4) But if the beneficial flora are somehow weakened, for instance by antibiotics, poor diet and/or stress, the opportunistic bacteria can grow out of control and lead to a number of gastrointestinal symptoms including bloating, abdominal pain, diarrhea and constipation. (5)

Gut Dysbiosis and IBS

Imbalances and disruptions in the gut microbiota are beginning to be recognised by the medical community as the missing link in understanding how IBS develops in the body.

Latest research has shown a clear distinction between the microbiota in the gut of patients with IBS and that of healthy people. Healthy individuals appear to have a more diverse gut microbiota than individuals who suffer from IBS. (6) Put simply, this means the composition of bacteria in the gut of someone with IBS is different from that of someone without digestive symptoms.

Studies have found a distinct imbalance in the microbiota of people with IBS, with:

  •        Decreased counts of bifidobacteria. (8)
  •        Increased levels of Clostridia spp.  (7)
  •        A decrease of coliforms, lactobacilli and bifidobacteria. (9)
  •        Reduced Bacteroides. (10)
  •        A 2-fold increase in the ratio of Firmicutes to Bacteroidetes. (11, 12)

In a study conducted on patients between 17 and 76 years old, dysbiosis was investigated in 236 IBS and 135 IBD patients who were diagnosed according to Rome II and III-criteria. A dysbiosis frequency of 73% was observed among IBS patients. Dysbiosis in healthy individuals occur at a rate of around 16%.  (13)

Other carbohydrate-utilizing gastrointestinal bacteria — namely, Dorea spp. — show significant increases in abundance in patients with IBS, these are the main gas-producing bacteria in the human gastrointestinal tract. The overproduction of gas is associated with IBS and this phenomenon could underlie flatulence and abdominal pain. (14)

A number of studies have found lactic acid-producing bacteria such as Lactobacillales were decreased significantly in IBS-Diarrhea patients. The decrease or elimination of lactic acid buildup will impair the intestinal defense barrier and increase osmotic load in the intestinal lumen, leading to more water staying  in the bowel and diarrhea.

Another study found that butyrate-producing bacteria such as Ruminococcaceae and Lachnospiraceae were decreased dramatically in diarrhea patients. Butyrate is a short chain fatty acid produced by certain gut bacteria when they ferment carbohydrates and is a preferred energy source for cells of the gut wall to maintain normal barrier function and also maintains gut homeostasis through anti-inflammatory actions. (15)

Alterations of intestinal microbiota in patients with chronic constipation can be characterized by a relative decrease in Lactobacillus, Bifidobacterium, Clostridium leptum, Faecalibacterium prausnitzii and Bacteroides spp.) and an increase of potentially pathogenic microorganisms (e.g. Pseudomonas aeruginosa and Campylobacter jejuni) (16,17,18)

The Roseburia–E. rectale group, a predominant butyrate-producing bacterial group of in the human gut were detected at significantly lower levels in IBS-C patients compared with Healthy Controls, which may explain the decrease in concentration of butyrate in IBS-C patients. (19,20)

What are the symptoms of dysbiosis?

  • Bloating, abdominal pain and cramping.
  • Constipation, diarrhea, or mixed bowel movements.
  • Burping and flatulence
  • Indigestion, reflux, heartburn.
  • Food intolerances.
  • Fatigue, brain fog
  • Anxiety, depression
  • Joint pain.
  • Skin conditions.

What are the causes of dysbiosis?

Factors that may disrupt your gut microbiota include:

  •        Antibiotics
  •        Diet
  •        Chronic stress
  •        Gastrointestinal infections
  •        Medications such as NSAIDs, PPI’s
  •        C-section birth
  •        Exclusive bottle feeding
  •        Altered gastric secretions (gastric acid, pancreatic enzymes, bile)

Antibiotics and dysbiosis

The use of antibiotics is by far the most common and significant cause of gut dysbiosis. (14) The alteration and disruption of the normal level of flora caused by antibiotics has been known for a long time. Antibiotics do this by inviting a secondary infection by harmful yeasts and pathogenic bacteria to take hold. (21,22)

Antibiotics kill all kinds of bacteria, both good and bad. They are indiscriminate in this regard and this causes many short-term as well as long-term side effects.

Studies have shown that, by taking a single course of antibiotics, you can lose the biodiversity and balance of your gut flora within as little as 3 – 4 days. Although broad-spectrum antibiotics are formulated to kill systemic infections, they also alter the gut flora. A study was carried out showing that the use of broad-spectrum antibiotics was linked with the development of IBS. (23)

How do I know I have dysbiosis?

A comprehensive stool analysis  gives the most in depth analysis of bacteria, both beneficial and pathogenic, and their levels in your gut, as well as yeast, worms, parasites and other digestive markers. Learn more about the test here.

How is dysbiosis treated?

Based on your stool test results we will have a better understanding of which species may be overgrown and which of your beneficial bacteria may need some help. The goal of rebalancing the intestinal flora is to make the conditions in the intestine more hospitable for the friendly intestinal flora, but not for the pathogenic bacteria. Our protocols use diet, herbal medicines and nutritional supplements to restore balance to your gut ecosystem.

  1. Removing foods from your diet that cause inflammation and feed bacterial/yeast overgrowths. Learn more about the eating plan here.
  2. Removing any overgrowths of bacteria and/or yeasts in your gut with herbal medicines..
  3. Restoring beneficial bacteria and re-establishing healthy bacterial balance in your gut with prebiotic fibres/foods and probiotic supplements/foods.
  4. Enhance gut immunity and repair the gut lining.

When conditions in your gut are improved then it naturally keeps an overgrowth of pathogenic bacteria at bay and healthy balance is restored.

What next?

To learn more about the testing and treatment options available it is recommended you take a free 15 minute phone consultation. During this call you can learn more about the programme and have all your questions answered. This call is to determine if we are a good fit for one another rather than a history or complete consultation. There is no obligation, and no strings attached.

It is quick and easy to book your free 15-minute phone consultation using the online calendar. Just click the button below, choose a date and time convenient for you, enter your details, and Matt will call you at your chosen time.

Book Free Phone Consult


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