IBS and Probiotics

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IBS and Probiotics

Research shows that people with IBS have lower than average amounts of the probiotic bacteria Lactobacillus and Bifidobacterium in their guts. Studies have also shown that by replenishing these good bacteria, probiotics can help relieve IBS symptoms such as irregular bowel movements, abdominal pain, and bloating.

Irritable Bowel Syndrome, IBS, is a very common disorder. The American College of Gastroenterology estimates that 10-15% of Americans suffer from IBS. IBS affects the gastrointestinal tract and includes symptoms such as abdominal cramping, changes in the frequency of bowel movements, as well as gas and bloating.

There is no “one” cause, but rather many factors that likely contribute to the onset of IBS. Our gut bacteria—especially the good bacteria called probiotics—play a central role. Several studies have shown that IBS is associated with an imbalance in our gut bacteria, often an overgrowth of bad bacteria and that symptoms can be improved by taking a high quality, multispecies and multistrain probiotic supplement.

In this post, we’ll take a look at what IBS is, some of the most common symptoms across the different types of IBS, possible causes, and how the use of probiotics could help.

What is IBS?

Irritable bowel syndrome is “a functional disorder of the gastrointestinal tract” with several subtypes. Researchers have identified multiple factors that may contribute to IBS, though the underlying cause is often not clear.

IBS Symptoms

Signs and symptoms include cramping, abdominal pain, bloating, gas, and diarrhea or constipation, or a combination of these.

Some patients only experience mild symptoms that come and go depending on other life circumstances such as stress and diet. Other patients, however, experience severe and debilitating symptoms and pain that have a severe impact on the quality of life, including becoming so severe that may cause some people to be unable to work.

Types of IBS

There are three types of IBS, each accompanied by slightly different symptoms.

IBS with diarrhea (IBS-D) is defined as a type of IBS in which abdominal pain or bloating symptoms happen along with loose and frequent bowel movements (stool frequency of more than 3 times per day).

IBS with constipation (IBS-C) is a type of IBS in which abdominal discomfort and/or bloating are accompanied by constipation. Constipation is defined by bowel movements less than three times per week.

IBS with both constipation and diarrhea (IBS-M) is a type of IBS in which abdominal pain or bloating happens along with experiencing hard, lumpy stools during at least 25% of bowel movements on symptomatic days, and experiencing loose, mushy stools during at least another 25% of bowel movements on symptomatic days.

Sad Girl Suffering From Irritable Bowel Syndrome

Possible Causes of IBS

To this day, there is no single cause for IBS. Instead, researchers have identified several possible factors that may contribute to this condition.

Imbalance in gut flora

A healthy balance of gut bacteria is critical to overall health and wellbeing. Our good gut bacteria - “probiotics”- play a central role in digestion, nutrient absorption, immune function, and even cognition.

When the healthy balance of probiotic bacteria in the gut is disrupted, it leaves opportunity for potentially harmful bacteria, viruses and fungi to grow. This leads to inflammation in the intestines, changes in the mucous layer that lines our intestines and can even damage the intestinal wall. Clinical studies have established a strong link between IBS and a reduction in the diversity and amount of good bacteria in the gut. One study found that “major functional dysbiosis was observed in constipated-irritable bowel syndrome gut microbiota.” Another study observed both changes in the gut flora as well as increased intestinal permeability and activation of the immune system.

Alterations in Gut Motility

Gut motility refers to the stretching and contracting of the muscles along the small and large intestine. These muscles move food through the digestive tract during the digestive process and play a key part in our bowel movements. Clinical studies have identified a link between changes in gut motility and IBS.

Constipation occurs when gut motility slows down. When gut motility speeds up,food moves through the intestinal tract faster than normal, leading to diarrhea.

Our gut bacteria play an important role in gut motility as well. An imbalance in gut bacteria may contribute to changes in motility.

Small Intestine Bacterial Overgrowth (SIBO)

Small Intestine Bacterial Overgrowth (SIBO) is defined as an overgrowth of bacteria in the small intestine. Clinical symptoms include indigestion, bloating, and abdominal discomfort.

In some cases, SIBO and IBS have been linked. One study found that symptoms of IBS improved after SIBO was treated with antibiotics. The relationship between SIBO and IBS remains controversial: Does one cause the other, or are they simply correlated?

Microscopic Colitis/Microscopic Inflammation

Microscopic colitis is a type of inflammation of the large intestine that can cause watery diarrhea and cramping. It's called microscopic because the inflammation is too small to see with the naked eye.

Microscopic colitis (MC) symptoms are similar in many cases to that of diarrhea-predominant irritable bowel syndrome (IBS-D). This is why researchers have investigated whether these two conditions might be related.

One clinical study included a large cohort of patients with microscopic colitis and assessed how many of these patients also fit the IBS diagnosis. The study concluded that “a considerable group of patients with microscopic colitis have diarrhea-predominant IBS- or functional diarrhea-like symptoms”.

However, a meta-analysis found that only one third of patients with microscopic colitis also had IBS and that the prevalence of IBS was not higher than in other patients with diarrhea.

Visceral Hypersensitivity

One of the hallmarks of Irritable Bowel Syndrome is visceral hypersensitivity. This describes the experience of pain within the inner organs (viscera) at a level that is more intense than normal. Only a subset of IBS patients (30-40%) have visceral hypersensitivity.

There are various potential causes for visceral hypersensitivity, including: changes in neurotransmitters and receptors within the cells of the gut wall, changes to their microRNA molecules, leaky gut, and inflammation.

Once again, the role of our gut bacteria should not be underestimated. An imbalance in gut bacteria, and the presence of potentially harmful pathogens often is associated with leaky gut and intestinal inflammation. In fact, several studies have pointed out a connection between gut dysbiosis (i.e., imbalance of gut bacteria) and visceral hypersensitivity.

Post-infectious IBS

Some people may develop post-infectious IBS. This is defined as the sudden onset of IBS following a stomach bug or severe food poisoning.

Research at Institut AllergoSan suggests that this post-infectious IBS is linked to changes in the composition of gut bacteria. Oftentimes, after a stomach bug or food poisoning, bacterial diversity and count are reduced, and more potentially harmful bacteria can thrive.


There is strong evidence that IBS is a “stress-sensitive” disorder. Stress can aggravate IBS symptoms. This is not surprising. Periods of stress can affect the composition of the gut flora, often decreasing bacterial diversity and quantity and damaging the gut barrier.

Furthermore, stress can impact gut motility, often leading to either constipation or diarrhea in affected individuals.


What are Probiotics?

Probiotics are good bacteria that naturally occur in a healthy human intestine. Our probiotic bacteria are essential to many important processes in the body, including healthy digestion, nutrient absorption, immune function and even cognitive processes such as concentration and mood.

Gut Flora

Billions of bacteria and other microorganisms live in our small and large intestines. This is called the gut flora or microbiota. Probiotics are part of this world of bacteria. There may also be some bad bacteria and microorganisms that could be potentially harmful to the body if left unchecked. Having enough good bacteria in your gut will help keep the bad ones under control.

Unfortunately, external factors such as food additives, allergens, chemicals, medications and stress can disrupt the healthy balance of probiotic bacteria in the gut. As a result, the environment in the gut becomes imbalanced. Probiotic dietary supplements aim to maintain and restore the natural diversity of your gut bacteria.

Gut Flora and IBS

Individuals with IBS have a different gut flora than healthy individuals. IBS patients often have reduced diversity and number of beneficial bacteria. In addition, a subset of IBS patients have an active overgrowth of potentially harmful bacteria (e.g., SIBO).

How do Probiotics Work with IBS?

Imbalances of the gut microbiota may contribute to IBS symptoms. Probiotics help maintain and restore the bacterial balance of our gut flora in a number of ways, not only by inhibiting the growth of harmful bacteria, but also by reducing inflammation, repairing gut barrier function and enhancing the immune system.

Beneficial Probiotic Species for IBS

Our gut contains 400-600 different strains of bacteria. Each of these strains has a different function, and the strains work together in teams for best results.

It is no surprise that there is not “one” single species or strain that will help with IBS. At OMNi-BiOTiC we believe that it is most effective to choose a probiotic that is specifically combined and tested in its final version to demonstrate results specific to your health needs.

Can Probiotics Improve IBS Symptoms?

Research shows that people with IBS have lower amounts of Lactobacillus and Bifidobacterium in their gut microbiome. Taking a high-quality probiotic supplement that contains some of these strains is beneficial to restoring a healthy balance of gut bacteria.


Overall Symptom Improvement

A high-quality, medically relevant multispecies and multistrain probiotic can help improve IBS symptoms. When choosing a probiotic supplement, make sure it’s free of any allergens, as these may worsen IBS symptoms.

In a recent study, OMNi-BiOTiC® STRESS Release was given to IBS-D patients for 4 weeks. Patients reported an 80% reduction in symptom severity, a significant improvement in bacterial diversity in the gut, improved gut barrier function, and short-chain fatty acid production. In addition, anti-inflammatory effects in the colon were noted.

Abdominal Pain

Abdominal pain is often caused by inflammation or the buildup of gas in the digestive tract. The buildup of gas in the intestines is often linked to problems with digestion.

Our gut bacteria play central role in digestion. If our gut bacteria are out of balance, this can impact digestion. Inflammation in the intestines may be caused by pathogenic bacteria. A high-quality, multispecies and multistrain probiotic can help restore a healthy bacteria balance, which can have a positive impact on abdominal pain.

Bloating and Gas

Bloating, gas and flatulence can be a sign that food is not digested properly and that the bacterial balance in the gut is out of balance. Our gut bacteria play a central role in digestion. An imbalance in gut bacteria is often linked to improper digestion, accompanied by bloating, gas and flatulence. A high-quality probiotic supplement can help improve digestion and bacterial balance.


Oftentimes, diarrhea is caused by harmful pathogens in the gut. For example, diarrhea is a common symptom of the harmful bacteria Clostridium Difficile and E. Coli. If the gut flora is out of balance, there is room for such harmful pathogens to grow.

A scientifically combined multispecies, multistrain probiotic can help fight off these harmful pathogens and restore healthy gut flora. There is also clinical evidence that certain bacterial strains influence gut motility. If the diarrhea is due to increased gut motility, a high-quality probiotic supplement may help rebalance gut bacteria and improve gut motility.


Just as with diarrhea, our probiotic gut bacteria play a helpful role in alleviating constipation. The beneficial bacteria in our gut help maintain a healthy mucous layer along the walls of the intestine, which helps move stool along in the colon.

Antibiotics and IBS

Antibiotics are a double-edged sword. They are necessary to help kill bacterial infections, including SIBO. In one clinical trial, IBS patients who received antibiotic treatment for SIBO reported an improvement in IBS symptoms.

At the same time, antibiotics upset the balance of bacteria in the gut. Given the important role of our gut bacteria, it is possible that taking antibiotics may increase IBS symptoms (e.g., diarrhea). When taking an antibiotic, it is recommended to supplement with a probiotic to rebuild the balance of bacteria in the gut, which is so key to maintaining a healthy body. OMNi-BiOTiC® AB 10 is designed to restore a healthy gut flora after antibiotic treatment.

Should You Take Probiotics if You Have IBS?

Yes! IBS is a functional disorder of the intestinal tract that goes along with changes in bowel movement and digestive discomfort. Our beneficial gut bacteria play a central role in maintaining healthy bowel movements, healthy digestion and overall intestinal health.

In addition, many conditions linked to IBS, such as SIBO and alterations in gut motility, relate back to a change in the gut flora, and an imbalance of gut bacteria. Furthermore, a systematic review of clinical studies has shown that a high-quality probiotic can have beneficial effects on IBS symptoms.

Use of a high-quality probiotic supplement has many health benefits. However, not all probiotics are alike. In fact, the term “probiotic” covers many different strains and types of bacteria. Make sure to consult your physician to see which probiotic supplement is the best fit for you to experience the positive effects of probiotics.



IBS is a complex syndrome that may have various underlying causes. Many IBS symptoms are connected to an imbalance of bacteria in the gut. Probiotics can help restore the healthy balance of gut bacteria. OMNi-BiOTiC® STRESS Release has been tested in clinical studies with IBS patients, with strong results: 80% reduction in symptom severity, improvement in gut barrier function, increase in bacterial diversity in the gut, and reduction in gut inflammation.

However, given the complexity of IBS, it is important to find what works for you. The Mayo Clinic suggests that IBS patients may also be able to manage their symptoms by: experimenting with additional fiber, avoiding problem foods that trigger the symptoms, eating on a regular schedule, and exercising.

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