Probiotics FAQ

Have you got questions about probiotics? Over the years, we have been asked about a number of things, so we’ve put this blog together with some of the most frequently asked questions. Your questions not here? Contact us and we’ll get an answer to you.

Q – What are they?

Each person has a small world inside of them. We have as many bacterial cells in our body (mostly in our digestive system) as we do human cells. These bacteria can have an enormous impact on a number of health measures. Probiotics are bacterial species that have been studied and shown to have health benefits when consumed.


Q – What are the benefits of probiotics?

More and more research is being carried out each year as the benefits of probiotics are tested. Current research shows that probiotics could have benefits for;

  • Digestion and absorption
  • Mental health conditions
  • Allergies
  • Immune function
  • ISB
  • Traveler’s diarrhea


Q – How do they work?

There are a number of mechanisms by which probiotics have been suggested to improve health.

They can directly modulate our immune system and can boost immune cells including natural killer cells, the Iga-producing cells as well as T lymphocytes.

They have an antimicrobial action. They produce antimicrobial substances and also compete with pathogens to adhere to the lining of our digestive system.

They can improve the intestinal barrier. Within our digestive tract, the lining of cells are held together by structural proteins. This barrier prevents certain substances and compounds from entering our circulation. Probiotics can enhance this barrier, as well as increase the mucosal layer which covers it.

Probiotics can also increase the amount of short chain fatty acids (SCFA) in our digestive system. These have been shown to have an anti-inflammatory effect throughout the body.


Q – Are they all the same?

If you look at the label of a probiotic product you will see the name of the bacterial strain that the product uses. For example, in our probiotic products we use the strains:

Lactobacillus acidophilus CUL 60

Lactobacillus acidophilus CUL 21

Bifidobacterium animalis subsp. Lactis CUL 34

Bifidobacterium bifidum CUL 20


The names are made up of the bacteria genus (e.g. Lactobacillus), species (e.g. acidophilus) and strain (e.g. CUL 60).

While some bacterial strains can have similar mechanisms and health benefits (particularly if they are the same species), some of the benefits have been shown to be strain specific.


Q – Which ones and how much?

Because many of the benefits are strain specific, it is important to select the right probiotic. In general, it has been found that those with more than one strain and species are more beneficial than those with a single strain and those that have strains from the Lactobacillus species appear to be the most effective (Chang et al., 2017). There have not been many studies that have looked at optimal doses of probiotics. However, a minimum of 10 billion CFU has been suggested (Ouwehand 2017) while the general recommendation is >20 billion CFU.


While these are general recommendations, the best advice would be to check each probiotic and see what research has been performed with that product, and what dosage was used. Many commercial products have not been used in research.


Q – Have the Lab4 strains been used in research? Probiotic-daily-25-billion

Lab4 is the proprietary group of probiotic bacteria, which was developed by Dr Nigel Plummer and his team of scientists at Cultech Ltd and has been used in probiotics products around the world for the past 10 years.

There are now 12 clinical studies supporting the use of Lab4 probiotics for a variety of functions in adults, children and babies. Carried out over the past 15 years, these studies have shown the benefit of the Lab4 and Lab4b consortia in supporting digestive health, immune health, performance and mood and cognition.

Specifically, the studies have shown the impact of probiotics on early immune system development, immunity in children, along

side antibiotics and in helping to prevent antibiotic resistance, irritable bowel syndrome (IBS), athletic performance, anxiety and attention.

Throughout these trials and 15 years of use in products, the Lab4 probiotic bacteria have been shown to be completely safe. This is further supported by The Swansea Baby Trial which involved both pregnant ladies and newborn babies. The approval of the Lab4b probiotics for use in this large trial with these two potentially vulnerable populations is testament to the efficacy of this group of bacteria.


Q – Are there any other benefits?

More recent research has also shown the Lab4 strains can also have a positive impact on sports performance.


  • When runners supplemented with Lab4 probiotics for 4 weeks and asked to run to exhaustion in the heat, they were able to run for ~15% longer compared to when they had taken the placebo (Shing et al., 2014)
  • In ironman triathletes, participants supplemented with probiotics or placebo for 12 weeks. Those taking probiotics had a 10% quicker overall race time than those on the placebo – although this did not reach statistical significance. Those taking probiotics also suffered from fewer and less severe gut symptoms (e.g. bloating, urge to defecate, nausea, etc.) during training compared to the placebo group. (Roberts et al., 2016)
  • Runners competing in the Marathon des Sables (often called the toughest race on the planet) had an overall race time that was 12% quicker after supplementing with Lab4 probiotics compared to placebo (Marshall et al.m 2017)

Yet to be published research has also shown that Lab4 can have benefits to athletes who consume carbohydrate drinks during exercise, as well as improve performance in marathon runners.


Take a look at the full PRP Probiotics range