Which Probiotics are for IBS?

Camilla Gray Nutritional Therapist Dip CNM - Diploma in Nutritional Therapy from the College of Naturopathic Medicine

When choosing a probiotic it is best to opt for one which has great research behind it. You want something that has been ‘scientifically tested’ - and rightly so! The best type of research to look for is a clinical trial because it shows how the probiotic performs in real people with real health conditions, compared to a placebo.

So, when choosing the best probiotic for IBS (Irritable Bowel Syndrome) it is a good idea to look for one which has been shown in clinical trials to be beneficial for this condition. There are 5 categories of IBS that we will explore in this article:

We also cover:

Continue reading to find out which are the best IBS probiotic strains for each IBS subtype.

Can probiotics help IBS?

Probiotics, also known as live cultures, have been shown in many clinical trials to support the health of those with IBS. Many people ask us 'Can you treat IBS with probiotics?' If you think you have IBS, you should always have your symptoms diagnosed by a doctor first; however, probiotics are a safe, natural option to try. Probiotics are fine to take alongside most prescription and over the counter medications for IBS.

Different probiotic strains can be beneficial for different symptoms of IBS. Clinical studies show the best probiotic supplements for IBS contain strains such as:​

Which probiotics have been researched for IBS-related symptoms?

First of all, when looking for the best probiotic to help with IBS, you should choose a probiotic with plenty of research that is of good quality. There are also different types of IBS, so it is essential to figure out what type you are dealing with. Then, you need to be aware that there are so many different types of probiotics (called different strains) and they all have different properties. In this article, we hope to make things clear for you by outlining the different types of IBS and which strains of probiotics have been shown to support each.

probiotic strains researched for IBS
Probiotic strains researched for IBS.

Key takeaway

Identify what type of IBS you are dealing with, then choose a supplement containing well-researched strains that have been shown to support those symptoms.

Probiotics for IBS-D 

Those with IBS presenting as frequent bouts of diarrhoea are suffering from IBS-D. If this is something you suffer from, you may consider the probiotic Saccharomyces boulardii which has been shown in many clinical trials to help support gut health in those with occasional diarrhoea. This is a unique probiotic microorganism because it is a yeast – in fact, it is the only yeast that is friendly enough to be called a probiotic. It has over 50 years of research and is recommended in many hospitals in countries throughout mainland Europe for people with diarrhoea. As well as diarrhoea caused by IBS it has also been shown to be beneficial for diarrhoea associated Inflammatory Bowel Disease (IBD), antibiotic-associated diarrhoea and traveller’s diarrhoea.

A 2021 meta analysis involving 42 RCTs reported S. boulardii as being amongst the best strains for IBS27S. boulardii showed significant improvements in abdominal pain relief frequency and general pain scores, particularly for individuals in the IBS-D subtype.

It is also worth considering taking a general probiotic product containing friendly bacteria alongside S. boulardii. As mentioned above, S. boulardii is a friendly yeast, and as such, has very different properties to friendly bacteria. For example, S. boulardii does not colonise in the gut, it is instead considered to be a transient probiotic which moves through the gut without staying for long. So, it’s a good idea to take a probiotic containing colonising friendly bacteria that can boost gut health in general and support the work of S. boulardii.

Healthcare practitioners can read more about S. boulardii on our Probiotics Database.

Pediococcus acidilactici CECT 7483, Lactobacillus plantarum CECT 7484 and Lactobacillus plantarum CECT 7485 have also been shown in a clinical trial to benefit those with IBS-D13. This trial measured improvements in the quality of life of the participants, in relation to their IBS symptoms, which is thought to be one of the most accurate ways of measuring the effectiveness of the treatment.

Key takeaway

If you suffer from IBS-D then consider taking Saccharomyces boulardii which has over 50 years of research behind it. You may find it helpful to take a general probiotic containing friendly bacteria alongside it.

Probiotics for IBS-C 

Those with IBS who tend to suffer with regularity issues and constipation are suffering from IBS-C. If this is something you suffer with, you may consider taking a natural supplement containing a specific probiotic strain called Bifidobacterium lactis BB-12® which has so many clinical trials supporting it, that it is thought to be the most well-researched strain in the whole Bifidobacteria genus. This strain has been shown to be particularly helpful for those with occasional constipation and promoting more regular bowel movements, which are easy to pass, as well as supporting gut health in general.

One clinical trial involved over 100 women with a tendency towards constipation who were given a supplement including Bifidobacterium lactis BB-12® and prebiotics14. Intestinal transit time (the time it takes for food to move through the gut and come out the other end as a bowel movement) decreased significantly. Those who took the B. lactis BB-12® supplement were no longer constipated and had normal bowel movements compared to those who took the placebo.

clinical trial

Healthcare practitioners can find out more about B. lactis BB-12® on the Probiotics Database.

Key takeaway

If you suffer from IBS-C, try taking a product that contains Bifidobacterium lactis BB-12® which has been shown to help relieve occasional constipation and support gut health in general.

Probiotics for IBS-A 

Many people with IBS find they have alternating constipation and diarrhoea. So, for a few days, you may be constipated, but then once the bowels get moving you find you have to run to the loo until things settle down again.

One option is to try a high-quality, general, daily probiotic. Two strains, Lactobacillus acidophilus NCFM® and Bifidobacterium lactis Bi-07® which can be found in Optibac Every Day EXTRA have been specifically trialled in those with IBS and shown to reduce bloating and abdominal distension15.

 In combination, they are ideal for anyone suffering from any type of IBS, not only to regulate bowel movements but to help specifically relieve the general symptoms of chronic bloating, abdominal distension, and abdominal cramps. Even on its own L. acidophilus NCFM® has been shown to be effective in improving symptoms of patients with IBS5.

Bifidobacterium infantis 35624 is also known as 'Bifantis’ and has been researched in those with Irritable Bowel Syndrome with positive results8. An 8-week trial with 75 participants associated B. infantis 35624 with a reduction in pain, discomfort, bloating and constipation. Healthcare practitioners can refer to Bifidobacterium infantis 35624, which has more information on this strain. 

A specific strain of the Lactobacillus plantarum species (L. plantarum Lp299v®) has also been clinically trialled on participants with IBS and has been shown to reduce IBS symptoms16. A 4-week clinical trial of 60 IBS sufferers showed that those in the probiotic group had a decrease in flatulence and pain and more consistent bowel movements. Again, healthcare practitioners can visit the L. plantarum Lp299v® to find out more.

It is worth noting that other L. plantarum strains will have been researched in different areas - e.g. L. plantarum CECT 7527, L. plantarum CECT 7528 and L. plantarum CECT 7529 have been clinically trialled and shown to reduce cholesterol levels, but are not beneficial for those with IBS. For more information on this topic take a look at are all probiotics the same?

Clinical trial results NCFM

The probiotic strain Bacillus coagulans Unique IS-2, which can be found in Optibac Probiotics Adult Gummies, has been researched for IBS in both adults and children. One study involving 136 adults with IBS found that eight weeks of supplementing with B. coagulans Unique IS-2 significantly reduced abdominal pain and increased the number of complete spontaneous bowel movements compared with placebo26.

Healthcare professionals can read more about Lactobacillus acidophilus NCFM®  and B. coagulans Unique IS-2 on the Probiotics Database. 

Key takeaway

If you suffer from IBS-A try taking a high-quality daily probiotic that contains strains like Lactobacillus acidophilus NCFM® and Bifidobacterium lactis Bi-07® that have been shown to regulate bowel movements and aid other symptoms of IBS like pain and bloating.

Probiotics for IBS-U 

If the previous types of IBS do not sound quite like you, then you might be struggling with IBS-U. This form of IBS is characterised by a stool consistency that doesn't fit into the other categories. In other words, you might experience both loose, watery stools and harder stools, but both less than 25% of the time. 

This type tends to be less common than the others but has similar causes, including diet, reduced gut motility, increased gastrointestinal sensitivity, or an imbalance of bacteria in the gut and bowels. There is also evidence to suggest a gut-brain connection17.

The probiotic strain Bifidobacterium lactis HN019 has been researched for IBS, and more specifically to improve intestinal transit time10. This can help with the sluggish gut motility often associated with IBS-U.

Key takeaway

If you suffer from IBS-U you may experience varying symptoms with sluggish gut motility. Try taking a supplement that contains Bifidobacterium lactis HN019 to aid motility and support other IBS symptoms.

Post-infectious IBS 

Approximately one in ten who suffer from IBS believe their symptoms began with an infectious illness. IBS symptoms can be experienced in the short or long term; however, bacterial gastroenteritis and parasitic infections are more likely to cause longer lasting IBS18.

It seems that there are a couple of risk factors for developing post-infectious IBS, including the duration of the illness, whether you are a smoker, female, suffer from depression, or experienced any adverse life events three months previously19.

If you have this type of IBS, you are more likely to suffer from diarrhoea or a mixed stool pattern.

Taking the probiotic yeast Saccharomyces boulardii can help aid the diarrhoea symptoms of the infectious illness itself and also support the IBS symptoms afterwards. It may also be prudent to take a general probiotic alongside to assist with other associated symptoms.

Key takeaway

If you’ve developed IBS symptoms after picking up a bug abroad, or after food poisoning, try taking Saccharomyces boulardii. You may also find it helpful to take another supplement alongside it, for supporting gut health in general.

IBS and bloating

Most people with all forms of IBS also suffer from some occasional bloating. At certain times the bloating can really flare up when aggravated by factors such as stress or eating particular foods, for example, gluten- or dairy-containing foods. However, many different high-quality probiotic strains have been shown to alleviate and prevent bloating, including Lactococcus casei Rosell-1058 and Bifidobacterium infantis 35624. These can help to aid the digestion of food by producing enzymes to break down starch and lactose. Learn more by reading: Probiotics for bloating.

At the end of the day, everyone is different, and IBS sufferers will have different gut floras to one another. With probiotics, it is often a case of trial and error to find which species and strains work for that individual. There is no harm, in 'mixing and matching' different products - in fact, this can often be the best way of catering for the specific needs of the individual. For more information on this topic, see Is it possible to overdose on probiotics?

Key takeaway

Certain foods and drinks can trigger IBS bloating, along with emotional triggers like stress. Probiotic strains such as Lactococcus casei Rosell-1058 and Bifidobacterium infantis 35624 can aid digestion and support bloating symptoms.

Top Tips for IBS
Top Tips

Prebiotics for IBS

A combination of probiotics and prebiotics, such as fructooligosaccharides, might also be beneficial for your IBS. Whilst typical sources of prebiotics, such as fermented foods or onions and garlic, can serve to worsen IBS symptoms, it is important to include prebiotics in your diet to best support your gut bacteria:

  • Prebiotics act as a food source for probiotics, and, as discussed above, probiotics can be extremely useful in helping to alleviate symptoms of IBS20.
  • In one study21, it was found that IBS-related anxiety was reduced after 4 weeks of taking a prebiotic galactooligosaccharide mixture.
  • You might consider finding ways of taking prebiotics that works for you, in foods like bananas and plantains for example, as these possess prebiotic qualities but at lower levels of fermentation.

Learn more about prebiotics by reading: What are prebiotics?

Key takeaway

Prebiotics are food for probiotics and can help aid IBS symptoms. However, they can be a double-edged sword for some so it’s important to find a source of prebiotics that work for you, whether it is in food form or supplemental form.

Can probiotics make IBS worse?

Probiotics are very well tolerated by the majority of people who take them. Those who have an extreme imbalance of good and bad bacteria in their gut, also known as dysbiosis, may find that initially taking a probiotic supplement that contains prebiotics causes an increase in gas and bloating. These side effects should subside within 48 hours in most people while the gut microbiome readjusts, but may last a little longer if the gut is severely imbalanced. If you can, it is worth persevering, either by lowering the dose or coming off for a few days before reintroducing them, once the gut has readjusted the pre and probiotics can start to exert their full benefits.

For those who are on a low FODMAP diet, prebiotic supplementation is generally avoided at this time, but a purely probiotic supplement would not cause symptoms to worsen.

Healthcare professionals may wish to read more about this over on our Probiotic Professionals site: Probiotics and Side Effects - an in-depth review

Key takeaway

We are all different with unique gut microbiomes, so a few people may notice some initial digestive changes when they first take a new supplement. This is more likely if you have never taken a probiotic before or if you have a significant imbalance of good and bad bacteria.

Probiotics and IBS in-depth

IBS affects our society in huge numbers - up to 20% of the UK population are sufferers, with women twice as likely to be affected as men. The most used diagnostic method for IBS is the Rome criteria, which classifies IBS into these subtypes:

IBS-D (diarrhoea dominant); IBS-C (constipation dominant); IBS-A or IBS-M (alternating or mixed) & IBS-U (unspecified).

Although there is no clearly defined cause of IBS, many sufferers often report that symptoms are exacerbated by dietary factors such as wheat and dairy products, high FODMAPs foods, and lifestyle factors such as high-stress levels, as well as an imbalance in good and bad bacteria in the gut. It can be a good idea to keep a food and symptom diary for a few weeks to see if you have any dietary triggers. 

food diary
Foods can often be a trigger for IBS so keeping a food diary can be helpful

Recent research may have found a link between IBS-D symptoms and a pathogenic bacterium called Brachyspira. This bacterium hides inside intestinal cells and is unaffected by antibiotic treatment. If more studies confirm this link between IBS symptoms and Brachyspira, researchers believe probiotics may become the future treatment22.

Several studies have documented the link between gut microflora and IBS symptoms Sufferers often have lower levels of beneficial gut bacteria e.g. Bifidobacterium species, and increased levels of gut pathogens e.g. Clostridium species. We have seen above how specific probiotics may support the reduction of specific IBS symptoms. Also supplementing with a high-quality probiotic may help to reduce IBS symptoms in the following ways:

  • Probiotic bacteria give a huge boost to the number of friendly bacteria in the gut, leaving less space for ‘bad’ microbes that may cause IBS symptoms.
  • Beneficial microflora help break down foods that may exacerbate IBS.
  • Healthy gut flora may play a part in modulating the nervous system in the gut, called the enteric nervous system, therefore reducing the impact of stress on the gut, which is a key factor for many people with IBS.

Key takeaway

IBS has no clear cause but can be triggered by food and drinks such as wheat and dairy, high FODMAP foods and emotional triggers like stress. Sufferers often have lower levels of beneficial gut bacteria, so supplementing with researched strains may help reduce symptoms.

NHS recommends probiotics for IBS

The NHS includes the use of probiotics as part of tips recommended to help relieve IBS symptoms23.

This is a big milestone in the world of probiotics because, although probiotics are routinely prescribed in many European hospitals, it wasn’t always part of the NHS recommendations. The NICE guidelines (National Institute for Health and Clinical Excellence), which provides evidence-based guidelines/framework that many medical and health care professionals work within, now recommends that probiotics can be used for at least 4 weeks for managing IBS related symptoms24.

NHS logo

The NHS website states that: "Probiotics may help reduce bloating and flatulence in some people with IBS."

The inclusion of probiotics for IBS relief was due to the result of a systematic review by Moayyedi et al., published in 2010, which concluded that probiotics were effective in the management of IBS25.

Key takeaway

Although it might take a little longer for probiotics to be recommended/prescribed by the NHS for other health issues, it is promising that the potential benefits of probiotics are being recognised and they are now being recommended for issues like IBS and symptoms of lactose intolerance.

Which probiotics are best for IBS?

Not sure which probiotic is best for your form of IBS? If you are unsure which type of IBS you have and what probiotic would be best for you, then it would be a good idea to opt for a high-quality daily product containing probiotics supported with clinical trials. My personal favourite strain for IBS is Bifidobacterium lactis HN019 which has been shown to help with:

  • Abdominal discomfort
  • Gas/Bloating
  • Poor gut motility
  • Loose stools
  • Bowel regularity

As you can see the clinical trial shows this is a great all-rounder and would be helpful to support all types of IBS, so ideally you would choose a daily product that has Bifidobacterium lactis HN019 in it.

Healthcare professionals can learn more about Bifidobacterium lactis HN019 on the Probiotics Database. 

So, to summarise, it appears that that probiotics do have a beneficial role to play in chronic disorders like IBS28. The specific probiotic strains you may wish to consider for IBS are:

  • For IBS-D & post-infectious IBS - Saccharomyces boulardii
  • For IBS-C - Bifidobacterium lactis BB-12®
  • For IBS-A - Lactobacillus acidophilus NCFM® 
  •  For IBS-U - Bifidobacterium lactis HN019

Please note: if you are struggling with IBS, we advise you to seek advice and assistance from your healthcare practitioner in all instances.

If you enjoyed this article, you may also like to read:

Natural Remedies for IBS

Healthcare professionals can find out more by reading the following article on the Probiotic Professionals site:

Probiotics for constipation


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