Irritable Bowel Syndrome (IBS) is a common disorder affecting millions of people worldwide, as covered in last weeks’ post. These include viral infections, small intestinal bacterial overgrowth (SIBO), enzyme insufficiency, hypochlorhydria and leaky gut. In addition, other factors such as gut motility, visceral hypersensitivity, changes related to the brain-gut axis and antibiotic use are also very relevant.

Alterations in the microbiome is a possible contributor to IBS. Studies comparing the gut microbiota of IBS patients to healthy controls suggests that people with IBS have an altered microbiota. It is thought that the use of probiotic supplements can improve IBS symptoms through manipulation of the gut microbiota.

Probiotics and IBS

Microbiome vs Microbiota

The body harbours a huge array of micro-organisms both inside and out. Together these organisms (bacteria, fungi, viruses, yeast) represent the human microbiota. Meanwhile the microbiome is all the genes your microbiota contain. These two terms are often used interchangeably.

A dysregulated microbiota is a key driver for not just IBS but most diseases. Simply addressing the imbalance in bacteria, can positively impact the gut, brain, hormones, weight, mood, exercise and so much more.

Ideally we want to ensure that diet is the first step in ensuring a healthy microbiome, but this can be challenging for people with IBS who might be removing key food groups that provide key nutrients to support the growth of beneficial bacteria. The focus of today’s post is to briefly touch on the use of probiotics for IBS.

What are probiotics?

The WHO defines probiotics as “live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host.”[3].

Probiotics are a type of organism in food or supplements that can help to boost the amount of beneficial bacteria in your gut. Other than supplements, food sources of probiotics include:

  • Yoghurt
  • Kefir
  • Kombucha
  • Kimchi
  • Tempeh
  • Miso
  • Sauerkraut
  • Natto

There is no doubt that probiotics can support health and wellbeing. The question is whether it is beneficial for IBS.

IBS and probiotics

Functions of probiotics

The main function of probiotics is to introduce beneficial bacteria into the gut. Thereby supporting the proliferation of friendly bacteria, which in turn exert a positive effect on the gut and body.  Some of the benefits include:

  • Suppress the growth and binding of pathogenic bacteria
  • Improve gut barrier function and thereby immune function
  • Probiotics secrete short chain fatty acids (SCFAs) that help to modulate immune function
  • Improve bowel motility (really important in SIBO)
  • Reduce inflammation and pain
  • Improve production of neurotransmitters
  • Produce vitamin B12, butyrate and vitamin K2
  • Produce, metabolise and clear hormones (which include your sex, stress, hunger hormones)

In my experience it all comes down to three things: survival, type and timing. Firstly, will the probiotic survive the journey into the gut. Secondly, what strains are used? Thirdly, are you at the right stage of your gut healing work to use probiotics?

Survival of probiotics

To make it to the intestine, probiotics must first pass through the stomach, which is an acidic and hostile environment. Consequently, this can kill the beneficial bacteria. It is believed that only a small percentage of probiotics actually make it through the stomach and into the intestine alive. There is however some evidence to show that even dead bacteria can still exert a positive effect, but sadly not for long.

Specific strains such as Bacillus coagulans, Saccharomyces boulardii, Bacillus subtilis, Lactobacillus plantarum, Bacillus clausii have a better chance of getting to the gut to colonise.

This is one of the many reasons I like Spore-based probiotics. Spores dramatically increases the strains of the bacteria in your gut. Better still the acidity of the gut doesn’t impact them. What I really like about them is that they are multi-functional and coming to think of it worthy of its own separate blog post (note to self).

Another option to consider are probiotics encapsulated during lyophilisation (freeze drying).

Some probiotics will come with instructions to keep in the fridge, it is best to avoid these as they don’t tend to survive the temperatures in the body. Instead look for a shelf-stable product that contains soil-based organisms.

When is it best to take your probiotic? I have heard and read so many different answers to this, but will continue to stick with the manufacturers suggestion or in the absence of this suggest to take it after your evening meal.

Type of probiotics 

Even though IBS is one of the most popular research targets for probiotics, the research outcomes have been quite varied. Consequently making it difficult to evaluate the efficacy of using probiotics for IBS.

Having read endless studies around probiotics for IBS, the take home message is that a multi-strain probiotic delivers greater symptom outcomes for people with IBS, compared to single-strain probiotics. This is when more than one strain of Lactobacillus is used and often in combination with Bifidobacterium.

A meta-analysis by Ford et al., looking at randomised control trials published between 1946 and 2013, emphasise that the use of multi-strain probiotics have a greater effect at reducing IBS symptoms. [11]

Personally I feel we need validated symptom assessment tools in well-established clinical trials in order to get a better understanding of how specific strains and combination of these impact IBS symptoms.

Timing of probiotics

In functional medicine, we use a very specific approach to address IBS and leaky gut. The 5R approach is a powerful tool that can help you to get to grips with your IBS. The problem with probiotics is that they can worsen symptoms in some individuals if used at the wrong time. Consequently, sensitive individuals who may have SIBO, severe dysbiosis, slow motility, enzyme insufficiency, hypoclorhydria, histamine may not tolerate probiotics well. As a result, the focus should be to address the first few steps of the 5R protocol before considering probiotics.

Just like FODMAP foods can worsen IBS symptoms, so can probiotics. People often report bloating, pain, distention, diarrhoea and or constipation. This is one of many reasons why it might be best to introduce probiotics during the latter stages of healing IBS. The exception here might be spore or yeast-based probiotics.

Here are a few of my favourite supplements that I have had good results with.

  1. Saccharomyces Boulardii (a yeast based probiotic) – Not to be used long term!
  2. MegaSporeBiotic
  3. Bio-Kult Advanced Multi-Strain Formulation
  4. Allergy Research Essential Biotics Complete
  5. Wild Nutrition General Multi Strain Biotic

In conclusion, my advice is to either consider spore based probiotics, which are better tolerated or a yeast-based probiotic like Saccharomyces Boulardii during the early stages. Ideally you want to work with a registered practitioner who can guide you through the 5R protocol and identify which probiotic is best to use at which stage of your healing.

Finally, you can purchase any of these probiotics here using the discount code STHU10.


Nutritional Therapist Cheshire, Health, Nutritionist Cheshire, Functional Medicine Cheshire, Rootcause Solution