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I suffered for years with the symptoms of irritable bowel syndrome (IBS).
Abdominal pains kept me awake at night.
I was bloated to the point I looked pregnant.
Passing stools was a major challenge, and I could be blocked up for days.
Then there was the fatigue, brain fog, nausea, depression and acne.
What was the specialist's response?
You have irritable bowel syndrome. Eat more fibre, take Metamucil and drink more water.
But, none of those things helped.
Until one day, with the help of a knowledgeable holistic health practitioner I discovered the root causes of my IBS symptoms. With a clear plan, dietary changes and some natural supplements I was able to address those causes and now I consider myself an ex-IBS sufferer!
You see, irritable bowel syndrome (also known as IBS) is a BS diagnosis!
It is a term used for a collection of symptoms (like abdominal pain, constipation, diarrhea and gas) with numerous underlying triggers and causes.
It is a "waste basket" diagnosis used when other conditions such as colitis, inflammatory bowel disease (IBD), colorectal cancer and coeliac disease have been excluded (hopefully). (1,2,3)
Unlike, those with inflammatory bowel disease (IBD), for example, IBS shows no visible signs of structural damage to the bowel.
IBS is therefore considered a functional gastrointestinal disorder, characterized by chronic, often disabling, abdominal pain and changes in bowel habits. (2,4,5)
What are the symptoms of IBS?
Common symptoms of IBS include:
Generalized abdominal pain or cramping
Constipation (difficulty emptying bowels, or infrequent bowel movements)
and/or
Diarrhea (loose stools, with or without a sense of urgency - having to rush to the toilet)
Some can alternate between constipation and diarrhea. (2)
Many with IBS or poor gut health also complain of:
Bloating (3,6)
Feeling of incomplete evacuation (7,9)
Mucus with bowel movements (8,9)
Worsening of symptoms after eating (8,9)
Excessive or smelly flatulence (gas) (9,10)
Indigestion (dyspepsia) (12)
Frequent burping or belching (9,10)
Nausea (10,13)
Chronic fatigue or low energy (14,15)
Depression and/or anxiety (16,17,18)
Muscle and joint pain or Fibromyalgia (19,20)
Brain fog or poor memory (21,22,23,24)
Skin issues such as acne, hives, psoriasis or eczema (25,26,27,28,29,30,31)
Allergies, sensitivities or intolerances - food or environmental (29,30,32)
Migraines or headaches (33,34,35)
Weight changes (36,37,38) - weight gain is more common with IBS, but weight loss can occur with dietary restrictions or unresolved diarrhea.
What are "red flag" or "alarm" symptoms?
Alarm symptoms, such as unintended weight loss, frequent watery diarrhea, anemia, and appearance of blood in stool, should trigger a clinician to consider an alternative diagnosis and investigate further. (2,3)
Symptoms that interfere with sleep, that develop after age 50 years, that occur in those with a family history of inflammatory bowel disease, colorectal cancer and/or coeliac disease should also make the clinician more wary. (3)
IBS can be debilitating & severely impact a person's quality of life
IBS digestive symptoms can vary widely, but abdominal pain is a hallmark of the condition and bloating has been found to affect more than 80% of people with IBS (5,6).
People with IBS often report a reduced quality of life, with abdominal pain being the most common disruptive symptom. (39,40 ).
One US study found IBS sufferers had more days off work (6.4 vs. 3.0) and days in bed, and reduced activities to a greater extent than non-sufferers. (41)
Sadly, another large study reported that people with IBS said they would give up an average of 25% of their remaining lives in order to be symptom-free! (42).
What are the types of IBS?
Subtyping of IBS is controversial, but is based on stool form, which can be aided by use of the Bristol Stool Form Scale. (4)
There are 4 types or sub-types of IBS: (3)
IBS-C = IBS with predominant Constipation (>25% hard stools, <25% loose stools)
IBS-D = IBS with predominant Diarrhea (>25% loose stools, <25% hard stools)
IBS-M = IBS with Mixed bowel habits (>25% loose stools, >25% hard stools)
IBS-U = Unclassified IBS.
How is Irritable Bowel Syndrome medically defined?
"The diagnosis of IBS is usually made by performing a careful review of the patient's symptoms, taking a thorough health history, evaluating the patient for the presence of warning signs, performing a guided physical examination, and using the Rome IV criteria". (5)
According to the Rome IV criteria the patient must have:
Recurrent abdominal pain, on average, at least 1 day per week in the last 3 months, associated with 2 or more of the following criteria:
– Related to defecation
– Associated with a change in frequency of stool
– Associated with a change in form (appearance) of stool
The criteria needs to be fulfilled for the last 3 months with symptom onset at least 6 months. (3,5,43)
So, usually, once other conditions such as coeliac disease, colon cancer and inflammatory bowel disease have been ruled out, everyone else who meets the following criteria are lumped under one umbrella term, IBS. (1,2,3)
Ultimately, IBS is a diagnosis of exclusion.
Yet it is a serious issue of epidemic proportions.
Prevalence and risk factors for IBS
IBS affects between one in 11 and one in 26 people globally, at any point in time. (44)
Some studies suggest it could be as high as 45% of the general population! (45).
It is reported to be one of the top reasons for visiting an general practitioner (GP) and the most common reason for visiting a gastroenterologist. (46, 47)
Although it is thought that up to 50% of people with symptoms of IBS do not even consult their General Practitioner. (48)
It is the second most common reason, after common flu, to be absent from work (1).
Women are more likely to experience IBS than men, in a ratio of 2:1. (1)
The peak of the disease often starts in early adulthood. (1)
IBS with diarrhea (IBS-D) was the most common subtype reported with the Rome IV criteria (1).
Women more commonly suffer from IBS-C and men from IBS-D (1).
Why are we told there is no cure for IBS and why use the term IBS, at all?
This is because there is not just one single cause or treatment, and determining the cause or causes in an individual can be tricky when relying on standard medical testing.
Furthermore, we like our labels. It reduces fear and uncertainty. We'd rather be told we have IBS, than be told "sorry, we don't know what's wrong with you".
Although a label provides comfort in the short term and makes it easier to talk about, it does little to empower an individual to find a long-term solution to their symptoms.
We may leave with a diagnosis, but no effective guidance on the next steps to take, and little desire to search out the root cause of the symptoms.
The IBS label implies that the problem has been identified, which is far from the truth.
IBS is NOT a cause, it is only a description of the symptoms (3,5).
What are the causes of IBS?
Fortunately over the past decade, there has been an explosion of research on gut health and the identification of specific diseases and disorders that can cause IBS symptoms.
Some of the conditions listed, such as endometriosis, or a parasitic infection, would ordinarily not be considered an IBS root cause, as they are stand alone conditions. However, they have similar symptoms to IBS and are frequently missed or not thoroughly investigated.
Also, there appears to be frequent overlap between IBS and other functional gastrointestinal disorders, urogenital pelvic disorders, and even possibly inflammatory bowel disease (when in remission). (2).
There are several mechanisms that are thought to contribute to IBS symptoms: (2,49,50).
disruption of the gut-brain axis
gut dysmotility (poor gut movement or motions)
increased pain sensitivity (visceral hypersensitivity and poor pain modulation)
low-grade mucosal gut inflammation
increased intestinal permeability (aka a "leaky" gut)
and an imbalanced gut microbiome (altered microbiota)
Some of the common underlying causes include: (Click the coloured links for more information on each).
Intestinal dysbiosis (i.e. a disrupted gut microbiome or imbalanced gut bacteria). There are various different manifestations of dysbiosis. This can be due to antibiotic or medication use, previous infection, poor diet and more. Common ones include:
Small Intestinal Bacterial Overgrowth (SIBO) - an overgrowth of bacteria in the small intestine. (51,52,53,54,55,56)
SIBO is thought to be one of the most common causes of IBS, with some indications it could be as high as a 78% incidence rate! (56)
Large intestinal bacterial overgrowth (LIBO) (55)
Candida or fungal overgrowth (Small Intestinal or large intestinal Fungal Overgrowth - SIFO or LIFO) (56,58,59)
"There is emerging literature that an overgrowth of fungus in the small intestine of non-immunocompromised subjects may cause unexplained GI symptoms." (59)
In one small study, 26% of people with unexplained GI symptoms had an overgrowth of fungus in the small intestines (SIFO). Another study found 25.3% had SIFO. (59)
Infectious or post-infectious IBS - due to pathogenic or disease-causing microorganisms (also a form of dysbiosis):
Parasitic infection (60, 61, 62, 63, 64)
Bacterial or viral infection e.g. Clostridium difficile
Post-infectious IBS begins after an episode of acute gastroenteritis, also referred to as a "stomach bug" or food poisoning, and is due to a bacterial or viral infection. (65, 66)
Clostridium difficile is a species of bacteria that is frequently hospital acquired and can cause severe diarrhea, and even psychological symptoms. (67)
Medication use
Certain medications can directly disrupt gut function or increase susceptibility to infection and bacterial or fungal overgrowth.
Of particular note are:
Proton pump inhibitors (PPIs) - used for reflux and heart burn (68,69)
Opioids
These include pain-relieving prescription drugs like codeine, morphine, oxycodone and vicodin. Plus, the recreational drug heroin. Constipation is a common symptom of opiate use. (70, 71,72)
Anti-biotics
Prolonged or broad-spectrum antibiotics have been shown to induce changes in the gut and increase susceptibility to certain infections. (73, 74, 75)
Non-steroidal anti-inflammatories (NSAIDs)
These include: aspirin (such as Disprin), ibuprofen (such as Nurofen), naproxen (such as Naprosyn), diclofenac (such as Voltaren), celecoxib (such as Celebrex).
As well as an increased risk of gastric ulcers, gastrointestinal bleeding, heart attack, and stroke, they may promote a "leaky gut" (increased intestinal permeability). (76, 77)
Food allergies, sensitivities and intolerances
"60% to 70% of IBS patients report a worsening of symptoms after meals, 50% to 70% report intolerance to various foods, and more than 70% believe that foods cause their symptoms." (78)
Distension of the gut, food hypersensitivity, and direct action of the food chemicals on the gut have been proposed as mechanisms by which food items might induce symptoms. (79, 80,81)
Foods commonly reported as symptom triggers include: fruits (citrus, banana), grains (wheat, barley, rye, oats, corn), vegetables (onions, peas, potatoes), dairy products (yogurt, milk, cheese, eggs, butter), legumes (beans, lentils), wine, chocolate, coffee, tea, and fried foods. (81, 82)
Double-blind oral food challenges have confirmed banana, coffee, corn, eggs, milk, peas, potatoes, and wheat as common triggers. (83)
Gluten, a component of wheat, barley and rye has also been shown to impact those with Irritable Bowel Syndrome. Studies have shown a gluten-free diet can have a significant effect on the reduction of symptoms. (84,85).
The term Non Coeliac Gluten Sensitivity (NCGS) refers to people who do not suffer from Coeliac disease (CD), but their symptoms improve by removing gluten from their diet. Clinically, they present with IBS-like symptoms, but even systemic manifestations (tiredness, headache, fibromyalgia-like joint or muscle pain, leg or arm numbness, brain fog, dermatitis or skin rash, depression, anxiety, and anaemia) can occur (86).
Nutrient deficiencies
These can perpetuate a vicious cycle of poor gut health. For example, Vitamin D and zinc deficiencies are known to interfere with gut function (87, 88).
Emotional stress
Stress is a known trigger as it impacts greatly on gut motility (motion) and "leakiness"; enzyme, bile and stomach acid secretions; and the diversity of the microbiome. But it's typically not the only cause (89).
Increased intestinal barrier permeability (leaky gut) - usually due to any of those mentioned above.
Malabsorption issues
Such as Bile Acid Malabsorption (BAM) which can cause diarrhea. (130)
Thyroid disease
Hypothyroid patients typically experience constipation. For those with hyperthyroidism, diarrhea is more likely. The cause is due the thyroid hormones impact on gut transit time. (131).
Nutrient deficiencies due to poor gut absorption can also lead to thyroid dysfunction.
Endometriosis
Women with endometriosis, can also experience IBS-like symptoms. (132, 133)
Often, more than one condition is involved, interacting in a way to produce a perfect storm of debilitating symptoms.
What tests are available to identify the root causes of IBS?
It is only in the past decade that we have gained access to more accurate and reliable testing.
Stool testing can now use DNA technology (PCR analysis) to identify previously undetected harmful bacteria, viruses and parasites. PCR (polymerase chain reaction) tests look for the genetic fingerprint of a wide range of pathogens and is far more sensitive test than the old fashioned technique of looking through a microscope.
The hydrogen and methane breath test used to diagnose a small intestinal bacterial overgrowth (SIBO) is now more fully understood and reliable (90).
There are even more accurate blood tests available for assessing food allergies and sensitivities, that include IgE, all subclasses of IgG and complement markers C3D or C1q (91).
However with newer, more advanced tests, comes a cost. A cost, governments are unwilling to pay at this point in time. So, many of these tests are not readily available through GPs, hospitals or even specialists.
For example, standard stool tests used by regular medical practitioners have been known to miss infections and certainly do not assess any microbial imbalance. The reference library used also determines if less common or emerging pathogenic species are detected (92).
Examination of multiple stools (with validated PCR probes and microscopy) is imperative if wanting to rule out parasitic infection, because intestinal parasites are intermittently shedded (93).
A comprehensive stool analysis is exactly that, comprehensive, and will use three samples, (not just one) to assess:
A large number of microbes (bacteria, viruses, yeasts, and parasites).
Certain digestive markers to indicate how well the food is being digested.
Inflammation levels by looking at markers such as lysozyme, lactoferrin, white blood cells and mucus.
Red blood cells and signs of bleeding in the gut.
Secretory IgA immune marker, which can indicate how well the gut mucus lining is acting as an immune defense barrier.
Short chain fatty acid (SFCA) levels, as good levels are essential for a healthy gut.
Levels of beneficial and commensal bacteria and an assessment of microbial balance.
GI 360 by Doctors Data is my preferred stool test.
Why doesn't the medical profession delve deeper into investigating and addressing the underlying causes?
Unfortunately only a small percentage of medical training involves exploring how nutrition, gut health, and our microbiome impacts our overall health and well-being.
Those interested in a more holistic approach need to undergo post graduate study in these areas, and then find a way to implement these discoveries into their very busy practices.
So time and knowledge is a factor, along with cost and access to more thorough testing.
Plus, the focus for the medical system is to typically uncover the more serious causes of the symptoms, such as bowel cancer, coeliac disease or inflammatory bowel disease.
Although invasive, gastroscopies and colonoscopies performed by gastroenterologist specialists are incredibly useful for ruling out these causes.
However, once an IBS diagnosis is given, the investigations usually stop there, and medications are frequently given to manage the symptoms. The sufferer may also be referred to a dietician to start a low FODMAP diet.
Can a low FODMAP diet help IBS sufferers?
A diet low in fermentable carbohydrates known as FODMAPs is frequently recommended for the management of irritable bowel syndrome (IBS) (94,95).
Several studies have suggested that avoiding high FODMAP foods can help manage bloating, stomach pains, flatulence, diarrhea and constipation (96, 97, 98).
Bacteria in the gut help break down food through a process called fermentation. When this occurs gas is released.
For some IBS sufferers, certain high FODMAP foods are thought to increase gas production in the gut, leading to distension and discomfort, because they are rapidly fermented and can be poorly absorbed.
This is likely to be exacerbated in the presence of a small intestinal bacterial overgrowth (SIBO), as there is more bacteria available for fermentation.
With SIBO, the type of bacteria in excess can also impact stool consistency. Those with predominantly methane gas-producing bacteria tend towards constipation. Those with mainly hydrogen gas-producing bacteria are more likely to have loose stools or diarrhea (99).
What does FODMAP stand for and what foods are high FODMAP?
FODMAP stands for fermentable oligo-, di-, mono-saccharides and polyols (100).
The four groups of FODMAPs and their main dietary sources include:
Oligosaccharides: fructans (FOS) and galacto- oligosaccarides (GOS) are subsets. Wheat, rye, legumes, lentils and various fruits and vegetables, such as garlic and onions.
Oligosaccharides are poorly absorbed in everyone, because humans lack the enzymes to break these carbohydrates down. Those with IBS tend to be more sensitive to their consumption and the gas produced.
Disaccharides: Lactose is the main carb and is found in milk and milk products, like yoghurt and cheese. People who lack the enzyme lactase will malabsorb lactose.
Monosaccharides: Fructose is the main carb. Found in various fruits including pear and mangoes, sweeteners such as honey and agave nectar, and products containing high fructose corn syrup.
Polyols: Certain fruits and vegetables including blackberries and lychee, as well as some artificial sweeteners like those in sugar-free gum and low calorie processed foods and drinks. Sorbitol and mannitol are the most common polyols in the diet.
A large range of foods contain these fermentable carbs, making a low FODMAP diet complicated and often very restrictive (101).
How to know which high FODMAP foods trigger symptoms
Determining which of the four groups is the most triggering requires a 3 step process over many months. This is usually done with the help of a dietician and the Monash University mobile phone app (101).
Stage one involves strict restriction of all high FODMAP foods for 2-6 weeks.
Stage two requires systematic reintroduction of specific high FODMAP foods one by one for three days each. This is a 6-8 week process.
During stage three foods that didn't trigger symptoms are reintroduced and a modified low FODMAP diet is continued, but is tailored to personal tolerance (101).
Could a low FODMAP diet do more harm than good?
Along with being complex and challenging, there are thoughts a low FODMAP diet could do more harm than good. This is because most FODMAPs are prebiotic fibre, meaning they support the growth of good, healthy gut bacteria (101,102).
Healthy bacteria in our gut not only help digest food (103), but they strengthen the integrity of the gut (104), produce vitamins (105) , harvest energy (106), protect against infection (107), regulate our immune system (108), make neurotransmitters essential for a stable mood (109), and so much more.
Furthermore when healthy bacteria are starved of prebiotic fibre, production of a key short chain fatty acid called butyrate is reduced. Butyrate helps to protect the gut lining , lower inflammation, heal a damaged gut, fuel the processes in the gut, aid insulin function, and even activate anti-oxidants (110, 111, 112, 113, 114, 115).
Going low FODMAP may reduce symptoms in some, but is it addressing the root cause?
If SIBO or a bacterial overgrowth from poor gut motility (motion) is an underlying factor, avoiding low FODMAP foods is simply a Band-Aid if not addressed.
Also, could any improvement be due to a reduction in gluten when on the diet?
Gluten containing wheat, barley and rye are high FODMAP or high fructan food groups. It is possible that the gluten protein triggers symptoms and not just fructans.
Given that the low FODMAP diet allows for small quantities of wheat, barley and rye to be consumed, IBS symptoms may still occur if gluten sensitive and it is not strictly removed from the diet.
Could a gluten free diet be the answer?
Studies have shown that a gluten free diet can improve symptoms in non-coeliac IBS sufferers, and return on reintroduction of gluten. (15, 116).
Research also indicates the existence of a non-coeliac gluten sensitivity with similar symptoms to IBS (116, 117).
Patients with IBS on a gluten diet also had higher small bowel permeability ("leaky" gut) than non-gluten consumers (16).
However, there are indications that fructan, rather than gluten induces symptoms in those with self-reported non-coeliac gluten sensitivity. (118,119)
Identifying the underlying root causes is not only critical to eradicating symptoms, but essential to improving long-term health.
The body's microbial community or collection of bacteria, viruses and fungi (that largely reside in our gut) are thought to influence our our mood, our behaviour, our weight, and our ability to fight infection.
70-80% of our immune system resides in our gut.
(120)
Poor gut health is known to increase the risk of infection (122), and studies suggest it may even play a role in dementia (121), obesity (122) , diabetes (123) , autism (124) , eczema (125) , allergies (126,127), asthma (128), autoimmune disorders (130), and so much more. (See You are 90% bugs, but are you the right kind?)
Accepting IBS as a life-sentence and managing symptoms without addressing the underlying causes, not only can doom someone to a lifetime of unnecessary suffering and frustration, but can potentially be dangerous!
Holistic practitioners understand that addressing poor gut health is essential to prevent or heal any chronic disease.
What is functional medicine and how can it help?
Functional Medicine utilizes the latest research findings on supplements, diet and other natural tools for restoring balance in the body. It asks why has function been lost and what can be done to restore function naturally?
A functional medicine practitioner takes a holistic approach and understands the connections between a large range of symptoms. Identifying the root causes is the priority in order to provide a long term solution to the clients health concerns. Specialized laboratory tests are often utilized to really dig deep and identify the underlying causes.
To become a certified functional medicine practitioner you need to be a qualified health professional in the first instance, and then complete hundreds of hours of additional training in functional medicine, nutrition & human physiology, before passing the final examinations.
So, what were my root causes and how did I rid myself of IBS for good?
Parasites, a gluten sensitivity and a candida overgrowth were my underlying causes. However if I was honest, at the true root of it all was many years of a high sugar poor quality diet, excessive alcohol consumption, stress and vitamin deficiencies (particularly zinc), use of the drug Roaccutane for acne, oral contraceptives and frequent antibiotics.
With the help of a holistic, functional health practitioner I went on a gut healing journey, changed my diet and cleansed my gut of parasites & candida with natural herbal supplements. It may sound simple, and it is, however it does require a clear, comprehensive and personalized plan. Plus, it is vital one sticks to the plan.
It's incredibly frustrating to hear so many be told they "just have IBS" and the only option is to try a low FODMAP diet and take potentially dangerous medications.
I challenge that narrative, as I have seen the life-changing results of a more holistic and thorough approach myself and with my clients over the years.
It is possible to no longer suffer with toilet troubles, frequent bloating or abdominal pain.
It is possible to feel healthy and happy again, with glowing skin and loads of energy.
Please, NEVER settle for IBS as a diagnosis.
Instead, uncover and address the underlying causes, thereby reducing the risk of further disease and improving not just IBS symptoms but overall health and well-being.
B.Sc, B. Chiro, CFMP, MNZCA
Certified Functional Medicine Practitioner & Chiropractor
Want to stop simply managing your IBS symptoms and instead address the root causes for a long term solution?
Then let's chat to see if my IBS & Gut Healing program is right for you. I'm based in Auckland, New Zealand but have clients from all over the world.
Book a FREE discovery call here.
REFERENCES:
1. New insights into irritable bowel syndrome: from pathophysiology to treatment. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6826071/
2. Irritable Bowel Syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5001845/
3. Irritable bowel syndrome: a clinical review https://pubmed.ncbi.nlm.nih.gov/25734736/
4. Functional bowel disorders https://pubmed.ncbi.nlm.nih.gov/16678561/
5. Rome Criteria and a Diagnostic Approach to Irritable Bowel Syndrome https://pubmed.ncbi.nlm.nih.gov/29072609/
6. Prevalence, characteristics, and impact of bloating symptoms in patients with irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/19124113/
7. Neuropathophysiology of irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/12184133/
8. Irritable bowel syndrome: Overview https://www.ncbi.nlm.nih.gov/books/NBK279416/
9. Irritable Bowel Syndrome: A Review Article https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4154827/
10. Overlapping gastroesophageal reflux disease and irritable bowel syndrome: increased dysfunctional symptoms https://pubmed.ncbi.nlm.nih.gov/20222167/
11. Prevalence of gastro-esophageal reflux-type symptoms in individuals with irritable bowel syndrome in the community: a meta-analysis https://pubmed.ncbi.nlm.nih.gov/23032982/
12. Systematic review and meta-analysis of the prevalence of irritable bowel syndrome in individuals with dyspepsia https://pubmed.ncbi.nlm.nih.gov/19631762/
13. Why Do Irritable Bowel Syndrome Women Often Have Nausea Symptom? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3271240/
14. Symptom frequency and development of a generic functional disorder symptom scale suitable for use in studies of patients with irritable bowel syndrome, fibromyalgia syndrome or chronic fatigue syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6656911/
15. Fatigue in Irritable Bowel Syndrome: A Systematic Review and Meta-analysis of Pooled Frequency and Severity of Fatigue https://pubmed.ncbi.nlm.nih.gov/27021828/
16. Anxiety and Depression in Irritable Bowel Syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5733421/
17. Prevalence of depression and anxiety in irritable bowel syndrome: A clinic based study from India https://pubmed.ncbi.nlm.nih.gov/23439939/
18. Gastrointestinal-specific anxiety: an important factor for severity of GI symptoms and quality of life in IBS https://pubmed.ncbi.nlm.nih.gov/20367800/
19. Risk for Irritable Bowel Syndrome in Fibromyalgia Patients https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5411228/
20. A systematic review of the association between fibromyalgia and functional gastrointestinal disorders https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7727037/
21. Brain fogginess, gas and bloating: a link between SIBO, probiotics and metabolic acidosis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6006167/
22. Cognitive performance in irritable bowel syndrome: evidence of a stress-related impairment in visuospatial memory https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3967841/
23. Brain fog and non-coeliac gluten sensitivity: Proof of concept brain MRI pilot study https://pubmed.ncbi.nlm.nih.gov/32857796/
24. Irritable Bowel Syndrome Is Associated with an Increased Risk of Dementia: A Nationwide Population-Based Study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4701489/
25. The relationship between acne vulgaris and irritable bowel syndrome: A preliminary study https://pubmed.ncbi.nlm.nih.gov/32463985/
26. Acne vulgaris, probiotics and the gut-brain-skin axis - back to the future? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3038963/
27. Chronic urticaria and irritable bowel syndrome: a cross-sectional study of 11 271 patients https://pubmed.ncbi.nlm.nih.gov/28906546/
28. Atopic Dermatitis in Adults and Irritable Bowel Syndrome: A Cross-sectional Study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749755/
29. Association between Allergic Diseases and Irritable Bowel Syndrome: A Retrospective Study https://pubmed.ncbi.nlm.nih.gov/30130792/
30. Association between Irritable Bowel Syndrome and Allergic Diseases: To Make a Case for Aeroallergen https://www.karger.com/Article/FullText/503629
31. Clinical Implications of Intestinal Barrier Damage in Psoriasis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7851376/
32. Food Allergy and Intolerance in IBS https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5358086/
33. Irritable Bowel Syndrome and Migraine: Bystanders or Partners? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3714407/
34. Migraine in young females with irritable bowel syndrome: still a challenge https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5741982/
35. Migraine and irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/16419571/
36. Obesity and irritable bowel syndrome: a comprehensive review https://pubmed.ncbi.nlm.nih.gov/25904828/
37. General and abdominal obesity in relation to the prevalence of irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/30657237/
38. Irritable Bowel Syndrome and Dietary Interventions https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6423692/
39. Abdominal pain impacts quality of life in women with irritable bowel syndrome https://www.ncbi.nlm.nih.gov/pubmed/16405544
40. https://www.ncbi.nlm.nih.gov/pubmed/12775997 Impact of irritable bowel syndrome: prevalence and effect on health-related quality of life
41. Irritable bowel syndrome in the United States: prevalence, symptom patterns and impact https://pubmed.ncbi.nlm.nih.gov/15932367/
42. International survey of patients with IBS: symptom features and their severity, health status, treatments, and risk taking to achieve clinical benefit https://www.ncbi.nlm.nih.gov/pubmed/19384249
43. What Is New in Rome IV https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5383110/
44. Global prevalence of irritable bowel syndrome according to Rome III or IV criteria: a systematic review and meta-analysis (2020) https://pubmed.ncbi.nlm.nih.gov/32702295/
45. Global prevalence of and risk factors for irritable bowel syndrome: a meta-analysis https://pubmed.ncbi.nlm.nih.gov/22426087/
46. Prevalence of irritable bowel syndrome: a community survey https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1324800/
47. An approach to the care of patients with irritable bowel syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7083544/
48. Review article: the economic impact of the irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/25199904/
49. Diet in irritable bowel syndrome: What to recommend, not what to forbid to patients! https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5467063/
50. Recent developments in the pathophysiology of irritable bowel syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4491952/
51. Small intestinal bacterial overgrowth https://pubmed.ncbi.nlm.nih.gov/20937459/
52. Small Intestinal Bacterial Overgrowth: Comprehensive Review of Diagnosis, Prevention, and Treatment Methods https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7386065/
53. Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome - An Update https://pubmed.ncbi.nlm.nih.gov/32754068/
54. Normalization of lactulose breath testing correlates with symptom improvement in irritable bowel syndrome. a double-blind, randomized, placebo-controlled study https://pubmed.ncbi.nlm.nih.gov/12591062/
55. Gastrointestinal bacterial overgrowth: pathogenesis and clinical significance https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3752184/
56. Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome: A Bridge between Functional Organic Dichotomy https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5347643/
57. Intestinal Fungal Dysbiosis Is Associated With Visceral Hypersensitivity in Patients With Irritable Bowel Syndrome and Rats https://pubmed.ncbi.nlm.nih.gov/28624575/
58. Candidiasis: predisposing factors, prevention, diagnosis and alternative treatment https://pubmed.ncbi.nlm.nih.gov/24789109/
59. Small intestinal fungal overgrowth https://pubmed.ncbi.nlm.nih.gov/25786900/
60. Protozoan parasites in irritable bowel syndrome: A case-control study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5680167
61. The relationship between intestinal parasites and some immune-mediated intestinal conditions https://pubmed.ncbi.nlm.nih.gov/25926937/
62. Irritable bowel syndrome and intestinal parasites: a view from South America https://pubmed.ncbi.nlm.nih.gov/27409092/
63. Parasitic infections in irritable bowel syndrome patients: evidence to propose a possible link, based on a case-control study in the south of Iran https://pubmed.ncbi.nlm.nih.gov/32487206/
64. Irritable bowel syndrome in Egyptian patients: plausible risk factors and association with intestinal protozoa https://pubmed.ncbi.nlm.nih.gov/30885054/
65. Post-infectious irritable bowel syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2721231/
66.The incidence and risk factors of post-infectious irritable bowel syndrome: a meta-analysis https://pubmed.ncbi.nlm.nih.gov/22024145/
67. Clostridium difficile infection https://pubmed.ncbi.nlm.nih.gov/27158839/
68. Dysmotility and proton pump inhibitor use are independent risk factors for small intestinal bacterial and/or fungal overgrowth https://pubmed.ncbi.nlm.nih.gov/23574267/
69. Intestinal Dysbiosis Secondary to Proton-Pump Inhibitor Use https://pubmed.ncbi.nlm.nih.gov/29316555/
70. The prevalence, severity, and impact of opioid-induced bowel dysfunction: results of a US and European Patient Survey (PROBE 1) https://pubmed.ncbi.nlm.nih.gov/18721170/
71. Gastrointestinal motility, dysbiosis and opioid-induced tolerance: is there a link? ht1ps://www.ncbi.nlm.nih.gov/pmc/articles/PMC7045338/
72. Morphine induces changes in the gut microbiome and metabolome in a morphine dependence model https://pubmed.ncbi.nlm.nih.gov/29483538/
73. Antibiotic-Induced Changes in the Intestinal Microbiota and Disease https://pubmed.ncbi.nlm.nih.gov/27178527/
74. Antibiotics and the Intestinal Microbiome : Individual Responses, Resilience of the Ecosystem, and the Susceptibility to Infections https://pubmed.ncbi.nlm.nih.gov/27738912/
75. Prolonged impact of antibiotics on intestinal microbial ecology and susceptibility to enteric Salmonella infection https://pubmed.ncbi.nlm.nih.gov/19380465/
76. Vascular and upper gastrointestinal effects of non-steroidal anti-inflammatory drugs: meta-analyses of individual participant data from randomised trials https://pubmed.ncbi.nlm.nih.gov/23726390/
77. Role of non-steroidal anti-inflammatory drugs on intestinal permeability and nonalcoholic fatty liver disease https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5473116/
78. The Science, Evidence, and Practice of Dietary Interventions in Irritable Bowel Syndrome https://www.cghjournal.org/article/S1542-3565(15)00248-7/pdf
79. Irritable bowel syndrome and food interaction https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4112903/
80. Food-related gastrointestinal symptoms in the irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/11244249/
81. Self-reported food-related gastrointestinal symptoms in IBS are common and associated with more severe symptoms and reduced quality of life https://pubmed.ncbi.nlm.nih.gov/23644955/
82. Food: the forgotten factor in the irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/21333905/
83. The role of diet in symptoms of irritable bowel syndrome in adults: a narrative review https://pubmed.ncbi.nlm.nih.gov/19559137/
84. Comparison between gluten-free regime and regime with gluten in symptoms of patients with irritable bowel syndrome (IBS) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6559066/
85. Irritable Bowel Syndrome and Gluten-Related Disorders https://pubmed.ncbi.nlm.nih.gov/32316404/
86. Non-coeliac gluten sensitivity: piecing the puzzle together https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4406911/
87. Vitamin D and the Host-Gut Microbiome: A Brief Overview https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7322162/
88. Contribution of Zinc and Zinc Transporters in the Pathogenesis of Inflammatory Bowel Diseases https://www.hindawi.com/journals/jir/2019/8396878/
89. Impact of psychological stress on irritable bowel syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4202343/
90. Breath Tests for the Non-invasive Diagnosis of Small Intestinal Bacterial Overgrowth: A Systematic Review With Meta-analysis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955189/
91. P88 Dietary Antigen Test (Serum) https://precisionpointdiagnostics.com/test/p88-dietary-antigen-serum/
92.Gastrointestinal Pathogens Panel https://www.merckmanuals.com/-/media/Manual/LabTests/GastrointestinalPathogensPanel.html
93. Improvement of routine diagnosis of intestinal parasites with multiple sampling and SAF-fixative in the triple-faeces-test https://pubmed.ncbi.nlm.nih.gov/17343076/
94. Irritable Bowel Syndrome and Dietary Interventions https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6423692/
95. Low-FODMAP Diet Improves Irritable Bowel Syndrome Symptoms: A Meta-Analysis https://www.mdpi.com/2072-6643/9/9/940
96. Does a diet low in FODMAPs reduce symptoms associated with functional gastrointestinal disorders? A comprehensive systematic review and meta-analysis https://pubmed.ncbi.nlm.nih.gov/25982757/
97. Fermentable carbohydrate restriction reduces luminal bifidobacteria and gastrointestinal symptoms in patients with irritable bowel syndrome https://pubmed.ncbi.nlm.nih.gov/22739368/
98. Diet low in FODMAPs reduces symptoms of irritable bowel syndrome as well as traditional dietary advice: a randomized controlled trial https://pubmed.ncbi.nlm.nih.gov/26255043/
99. Low-FODMAP Diet for Treatment of Irritable Bowel Syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3966170/
100. Personal view: food for thought--western lifestyle and susceptibility to Crohn's disease. The FODMAP hypothesis https://pubmed.ncbi.nlm.nih.gov/15948806/
101. Irritable Bowel Syndrome and Dietary Interventions https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6423692/
102. The bifidogenic effect of inulin and oligofructose and its consequences for gut health https://pubmed.ncbi.nlm.nih.gov/19690573/
103. Role of the gut microbiota in nutrition and health https://www.bmj.com/content/361/bmj.k2179
104. Modulation of intestinal barrier by intestinal microbiota: pathological and therapeutic implications https://pubmed.ncbi.nlm.nih.gov/23089410/
105. Role of the gut microbiota in human nutrition and metabolism https://pubmed.ncbi.nlm.nih.gov/24251697/#
106. The role of short-chain fatty acids in the interplay between diet, gut microbiota, and host energy metabolism https://pubmed.ncbi.nlm.nih.gov/23821742/
107. Interactions between the microbiota and pathogenic bacteria in the gut https://www.nature.com/articles/nature18849
108. How colonization by microbiota in early life shapes the immune system https://pubmed.ncbi.nlm.nih.gov/27126036/
109. Neurotransmitter modulation by the gut microbiota https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6005194/#
110. Formation of short chain fatty acids by the gut microbiota and their impact on human metabolism https://pubmed.ncbi.nlm.nih.gov/26963409/
111. Intestinal health functions of colonic microbial metabolites: a review https://pubmed.ncbi.nlm.nih.gov/21840809/
112. Butyrate modulates oxidative stress in the colonic mucosa of healthy humans https://pubmed.ncbi.nlm.nih.gov/19108937/
113. Formation of short chain fatty acids by the gut microbiota and their impact on human metabolism https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939913/
114. Regulation of immune cell function by short-chain fatty acids https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4855267/
115. Potential beneficial effects of butyrate in intestinal and extraintestinal diseases https://pubmed.ncbi.nlm.nih.gov/21472114/
116. Evidence for the Presence of Non-Celiac Gluten Sensitivity in Patients with Functional Gastrointestinal Symptoms: Results from a Multicenter Randomized Double-Blind Placebo-Controlled Gluten Challenge https://pubmed.ncbi.nlm.nih.gov/26867199/
117. Evaluation of Non-Celiac Gluten Sensitivity in Patients with Previous Diagnosis of Irritable Bowel Syndrome: A Randomized Double-Blind Placebo-Controlled Crossover Trial https://pubmed.ncbi.nlm.nih.gov/32155878/
118. Fructan or FODMAPs, Rather Than Gluten, Induces Symptoms in Patients With Self-Reported Non-Celiac Gluten Sensitivity https://pubmed.ncbi.nlm.nih.gov/29102613/
119. Fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), but not gluten, elicit modest symptoms of irritable bowel syndrome: a double-blind, placebo-controlled, randomized three-way crossover trial https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8827068/
120. Aspects of Gut Microbiota and Immune System Interactions in Infectious Diseases, Immunopathology, and Cancer https://www.frontiersin.org/articles/10.3389/fimmu.2018.01830/full
121. Relationship between dementia and gut microbiome-associated metabolites: a cross-sectional study in Japan https://www.nature.com/articles/s41598-020-65196-6#
122. New-found link between microbiota and obesity https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4644874/
123. Role of gut microbiota in type 2 diabetes pathophysiology https://www.thelancet.com/journals/ebiom/article/PIIS235239641930800-X/fulltext
124. Alteration of Gut Microbiota in Autism Spectrum Disorder: An Overview https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7350540/
125. Gut microbiota profile in children affected by atopic dermatitis and evaluation of intestinal persistence of a probiotic mixture https://www.nature.com/articles/s41598-019-41149-6
126. The gut microbiota, environmental factors, and links to the development of food allergy https://clinicalmolecularallergy.biomedcentral.com/articles/10.1186/s12948-020-00120-x
127. Allergy and the gastrointestinal system https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2515351/
128. The Role of the Microbiome in Asthma: The Gut–Lung Axis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6337651/
129. The Dynamic Interplay between the Gut Microbiota and Autoimmune Diseases https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6854958/#
130. Prevalence of, and predictors of, bile acid malabsorption in outpatients with chronic diarrhea. https://pubmed.ncbi.nlm.nih.gov/22765392/
131. The thyroid and the gut. https://pubmed.ncbi.nlm.nih.gov/20351569/
132. Endometriosis in patients with irritable bowel syndrome: Specific symptomatic and demographic profile, and response to the low FODMAP diet https://pubmed.ncbi.nlm.nih.gov/28303579/
133. Endometriosis and irritable bowel syndrome: a systematic review and meta-analysis https://pubmed.ncbi.nlm.nih.gov/32949284/