The Best Probiotics for IBS, According to a Nutritionist

Irritable bowel syndrome, known as IBS, is an increasingly common disorder of the digestive system affecting up to 20% of the UK population, with women twice as likely to be affected as men. There is no known medical cure or specific cause, and every individual's symptoms can be different, so IBS treatment typically focuses on symptom management. However, symptoms may be exacerbated by foods such as wheat and dairy products, high FODMAP foods, and lifestyle factors such as stress, or an imbalance of good and bad bacteria in the gut⁵. 
Therefore many people find that diet and lifestyle improvements can provide IBS relief, and it can be a good idea to keep a food and symptom diary for a few weeks to see if if certain foods trigger your symptoms. Natural supplements are also very popular, with probiotics for IBS becoming a go-to supplement for many sufferers.

So probiotics and IBS are currently a huge area of interest, but how do you know which probiotics are good for IBS symptoms, or which type of IBS you have? There are different types of IBS, and the most used method for diagnosing IBS is the Rome criteria, which classifies IBS into these different categories - click on the one which suits your symptoms best, or watch my short video below:

• IBS-D – Diarrhoea predominant
• IBS-C – Constipation predominant
• IBS-A – Alternating constipation & diarrhoea
• IBS-U – Unspecified & varying symptoms
• Post-infectious IBS

If you have a general question about IBS, check out our information sections below:

• Do probiotics help IBS?
• Can probiotics make IBS worse?
• IBS and bloating
• Prebiotics for IBS
• NHS recommends probiotics for IBS
• Which probiotics are best for IBS

Do probiotics help IBS?

We're often asked questions about probiotics and IBS, such as "Can you treat IBS with probiotics?", "Should IBS sufferers take probiotics?", and simply "Are probiotics good for IBS?"! The answer is that probiotics have been shown in many clinical trials to help the symptoms of IBS, and most sufferers find them useful. Even the NHS recommends probiotics for IBS - they are fine to take alongside most prescription and over the counter medications for IBS, and are a safe, natural option to try. However, if you think you have IBS, you should always have your symptoms diagnosed by a doctor first.

But how do probiotics help IBS? Probiotics may help IBS because the condition has been associated with an imbalance in the gut microbiome⁵, the name for the populations of bacteria that live in the gut. Read more about the gut microbiome in this article: All About the Microbiome. Recent research seems to confirm this, indicating a link between IBS-D symptoms and a harmful bacteria called Brachyspira^22​. IBS sufferers often have lower levels of good gut bacteria e.g. Bifidobacterium species, and increased levels of bad bacteria, known as pathogens, with some of the best-known being from the Clostridium species. 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 bacteria help break down foods that may trigger IBS symptoms.
• A healthy gut microbiome may play a part in reducing the impact of stress on the gut, which is a key factor for many people with IBS.

Read more about the gut-brain connection in this article: The Gut-Brain Axis

When choosing a probiotic supplement for IBS, it is important to select one which is supported by good quality research. It should contain probiotic strains (also known as 'friendly bacteria' or 'live cultures') which have been ‘scientifically tested’ in clinical trials rather than just laboratory studies. Clinical trials show how the probiotic performs in real people for typical symptoms of IBS, such as constipation, bloating, or diarrhoea. Different probiotic strains can be beneficial for different symptoms of IBS, as each strain can have unique properties.

Clinical studies show the best probiotic supplements for IBS contain strains such as:

• Saccharomyces boulardii
• Bifidobacterium lactis BB-12^®
• Lactobacillus acidophilus NCFM^®
• Bifidobacterium lactis Bi-07^®
• Bifidobacterium infantis 35624
• Bacillus coagulans Unique IS-2
• Bifidobacterium lactis HN019
• Lactobacillus plantarum Lp299v^®

Read on to find out more about these strains, or if you're short on time, why not watch the video below.

In the video, I give a brief overview of the best strains to use for the most common types of IBS.

 

Can probiotics make IBS worse?

Probiotics are natural and very well tolerated by the majority of people who take them. But people who have an extreme imbalance of good and bad bacteria in their gut, also known as dysbiosis, may notice some changes in their digestive system when they first start to take a probiotic supplement. 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.  Probiotic supplements which contain prebiotics may also cause an increase in gas and bloating, especially in those who are sensitive to certain carbohydrates. For those who are on a low FODMAP diet, prebiotic or synbiotic supplementation is generally avoided at this time.

Read more about prebiotics and FODMAPs in What are Prebiotics?

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

Probiotics for IBS-D

If your doctor diagnoses you with IBS and your primary symptom is diarrhoea, then you have IBS-D. Saccharomyces boulardii is one of the best probiotics for IBS-D symptoms.

This unique probiotic is in fact a yeast, the only yeast 'friendly' enough to be called a probiotic.S. boulardii has over 50 years of research supporting its use, and is recommended in many hospitals worldwide for diarrhoea. A 2021 review of 42 clinical trials confirmed S. boulardii as one of the best probiotic strains for IBS diarrhoea²⁷. The review showed that S. boulardii offered significant improvements in abdominal pain and frequency of bowel movements for individuals with IBS-D. As well as IBS-D, it has also been shown to be beneficial for diarrhoea associated with Inflammatory Bowel Disease (IBD), antibiotic-associated diarrhoea and traveller’s diarrhoea. Healthcare practitioners can read more about probiotics for IBD on the Probiotic Professionals site.

As S. boulardii is a friendly yeast, it has very different properties to friendly bacteria; it's a 'transient' probiotic meaning that it does not colonise for long in the gut. Therefore it’s a good idea to take a probiotic containing colonising friendly bacteria alongside S. boulardii as they work together. For this, use one of the probiotic strain recommendations in the IBS-A section.

The probiotic strains Pediococcus acidilactici CECT 7483, Lactobacillus plantarum CECT 7484 and Lactobacillus plantarum CECT 7485 have also been researched and shown to be good probiotics for IBS-D¹³. This trial measured improvements in the quality of life of the participants, in relation to their IBS diarrhoea symptoms, which is thought to be one of the most accurate ways of measuring the effectiveness of the treatment.

However, Saccharomyces boulardii is the primary probiotic recommendation for IBS-D. Healthcare practitioners can read more about S. boulardii and using probiotics for diarrhoea and upset stomachs on the Probiotics Professionals site.

Probiotics for IBS-C

If you have IBS which presents with regularity issues and constipation, this is known as IBS-C. There are a couple of probiotic strains which have been particularly researched for constipation: Bifidobacterium lactis BB-12^® and Bifidobacterium lactis HN019. Bifidobacteria like to live in the large intestine where the stool is formed, so they tend to be the most researched probiotics for regularity issues.

Bifidobacterium lactis BB-12^®,  is thought to be the most well-researched strain in the whole Bifidobacteria family, and has been particularly researched in those with constipation^3,4. It promotes more regular bowel movements, which are easier to pass, as well as supporting gut health in general.

In one clinical trial, over 100 women with constipation were given a supplement containing Bifidobacterium lactis BB-12^® and prebiotics¹⁴.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.

The illustrated clinical trial used Bifidobacterium lactis BB-12^® in combination with a prebiotic; however, prebiotics don't suit everyone who suffers from IBS. Read more about prebiotics and IBS below.

The probiotic strain Bifidobacterium lactis HN019 has been researched for all symptoms of IBS, and has also been shown to improve bowel regularity¹⁰. IBS-C sufferers who prefer to avoid prebiotics may get on better with a supplement containing Bifidobacterium lactis HN019 without added prebiotics.

Healthcare professionals can learn more about using probiotics for constipation on the Probiotic Professionals site, and read the rest of the research involving Bifidobacterium lactis BB-12^® and Bifidobacterium lactis HN019 on the Probiotics Database. 

Probiotics for IBS-A (also known as IBS-M)

Many people with this type of the condition find they have alternating symptoms of IBS diarrhoea, bloating, pain, and constipation. This form of IBS is known as IBS-A (alternating) or IBS-M (mixed symptoms). For the relief of this IBS variant, it can be hard to know which symptom to target, but the best first step is to try a high-quality, general, daily probiotic for all-round gut-support, as an imbalanced gut bacteria populations are thought to be a factor in all types of IBS⁵. Two strains, Lactobacillus acidophilus NCFM^® and Bifidobacterium lactis Bi-07^® have been specifically trialled in those with IBS and found to not only regulate bowel movements²⁹ but also for the relief of IBS bloating, abdominal distension, and abdominal cramps¹⁵. Even on its own Lactobacillus acidophilus NCFM^® has been shown to be effective in improving various symptoms of patients with IBS^5,6. 

Healthcare professionals can read more about Lactobacillus acidophilus NCFM^® and Bifidobacterium lactis Bi-07^® on the Probiotics Database.

Whilst Lactobacillus acidophilus NCFM^® and Bifidobacterium lactis Bi-07^® are the most recommended strains for all-round IBS support, there a few other probiotic strains which can be considered:

The probiotic strain Bacillus coagulans Unique IS-2 is often used in 'gummy' probiotic supplements so is popular with people who find this format easier to take. The strain has been studied for the support of IBS symptoms in both adults and children. In one study involving 136 adults with IBS were given B. coagulans Unique IS-2 for eight weeks. A significant reduction in abdominal pain and an increase in the number of complete spontaneous bowel movements was noted, compared with placebo26. Healthcare practitioners can visit B. coagulans Unique IS-2 to find out more about the research using this strain.

Bifidobacterium infantis 35624, also known as 'Bifantis’, 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 diarrhoea, bloating, and constipation and 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. Healthcare practitioners can visit this page on the Probiotics Database L. plantarum Lp299v^® to find out more about related research.

Probiotics for IBS-U

If the previous types of IBS do not sound quite like you, then you might be struggling with IBS-U (Undefined or Unclassified). This form of IBS is characterised by a stool consistency that doesn't fit into the other categories.Sufferers may experience both loose, watery stools and harder stools, but both less than 25% of the time. This IBS type tends to be less common than the others but has similar causes, including diet or an imbalance of bacteria in the gut and bowels. There is also evidence to suggest a gut-brain connection¹⁷.

Again, as with IBS-A/M above, it's best to begin supporting this type of IBS with probiotic strains which have been shown to help with a variety of symptoms, such as Lactobacillus acidophilus NCFM^® and Bifidobacterium lactis Bi-07^®. After supplementing with these strains for a month or so, symptoms may improve fully, or begin to trend more towards one symptom, then it will be possible to add in more specific strains for more targeted support. It's also wise to consider triggers so keeping an IBS symptom diary can be helpful.

Post-infectious IBS

Approximately one in ten people who suffer from IBS believe their symptoms began with an upset stomach. Serious infections such as gastroenteritis or parasitic infections are more likely to cause this sort of 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 address the cause of the infectious illness³⁰ itself and also support the IBS symptoms afterwards. It may also be prudent to take a general probiotic (see the strains recommended in the IBS-A section) alongside S. boulardii for all-round gut support.

IBS and bloating

People with all forms of IBS may also suffer from occasional bloating. It can be aggravated by factors such as stress or eating particular foods which challenge the digestive system²³, for example, gluten- or dairy-containing foods. However, as mentioned, many different high-quality probiotic strains have been shown to alleviate and prevent pain and IBS bloating, including Lactobacillus acidophilus NCFM^®, Bifidobacterium lactis Bi-07^{® 15} and Bifidobacterium infantis 35624⁸. Strains like Lactococcus casei Rosell-1058 aid the digestion of problem foods 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 bloating 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 if this works for you. You can't take 'too many' probiotics. For more information on this topic, see Is it possible to overdose on probiotics?

Prebiotics for IBS

Due to some prebiotic foods causing adverse reactions in those with IBS, we often get asked "Are prebiotics good for IBS" and if so "Which are the best prebiotics for IBS?".

If you experience bloating or digestive discomfort when eating particular prebiotic foods, you may be wondering whether to choose a prebiotic or probiotic for IBS, or a combination called a synbiotic without irritating your gut.

If you’re highly sensitive to foods that fall into the high FODMAP category, such as garlic, onions, apples, and leeks I firstly recommend working with a professional to try a low FODMAP diet to help calm your gut. During the elimination phase (which should only be a total of 4 weeks) you will be advised to avoid most prebiotic supplements.

For those who are mostly fine with prebiotic foods, what prebiotic supplements for IBS are best? Well, research shows that high dose synbiotic supplements including Fructooligosaccharides (FOS) were superior to placebo in improving bowel symptoms and fatigue in those with IBS²⁰. Prebiotics for IBS-C can be supportive as FOS is a source of soluble fibre that adds bulk and absorbs water to help soften the stool, it also helps encourage peristalsis which is the movement of food through the gut. Prebiotics such as FOS will also stimulate the growth of other beneficial bacteria which is already present in the gut.

Prebiotics for IBS and bloating:

• If you’re worried that introducing prebiotics for IBS will cause bloating, start low and slow! Taking them in the evening before bed can help too.
• Prebiotics are food for your gut bacteria and significantly increase levels of Bifidobacteria in those with IBS²¹
• When it comes to a probiotic vs prebiotic for IBS, you may need to experiment to see what suits you best.

Learn more about prebiotics, prebiotic foods, and FODMAP diets by reading: What are prebiotics?

 

NHS recommends probiotics for IBS

The NHS suggests that probiotics may help to help relieve IBS symptoms^23,31. In the UK, a 2022 report found that the cost of IBS to the NHS is £1.2-£2 billion per year³⁴. NHS online suggests that 75% of people manage IBS symptoms with self-care

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 symptoms^24.

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

Which probiotics are best for IBS?

IBS has a broad range of symptoms, and we've learned that you should look for supplements containing well-researched probiotic strains which have been found to offer benefits for your particular symptoms. It can also be worthwhile taking a high-quality daily product for all-round gut support alongside your specific strains. My personal favourite 'all-rounder' strain for IBS is Lactobacillus acidophilus NCFM^®  which has been shown to help with a variety of typical IBS symptoms:

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

Research^15,29 shows this strain is a great all-rounder and would be helpful to support all types of IBS, so ideally your daily product would have this strain in it. But a review of all available research to date confirms that specific probiotics have a beneficial role to play in chronic disorders like IBS²⁸, and people often take an all-round product for general gut support alongside one containing strains to support their specific type of IBS, such as the following:

• For IBS-D & post-infectious IBS - Saccharomyces boulardii
• For IBS-C - Bifidobacterium lactis BB-12^®

Please note: if you are experiencing severe IBS symptoms, you must always speak to your doctor for advice.

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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