Specific probiotic strains for specific conditions

At OptiBac Probiotics we specialise entirely in probiotics, and in particular we use specific probiotic strains to target different health conditions. Recognising that different types of probiotics can have different beneficial effects on the body (and that growing research continues to demonstrate this), we aim to offer each of our customers a specific probiotic supplement to support their individual health needs. When it comes to probiotics, it is not a question of 'one-size-fits-all'!

What is a probiotic strain?

Many people (healthcare professionals included) misunderstand the definition of a probiotic 'strain'. Read on to make sure you are in the know.

The term ‘strain’ refers to a biological variety within a species; a species in turn, exists within a genus. For example in our product 'One week flat', the name Lactobacillus acidophilus Rosell-52 tells you the name of the genus (Lactobacillus), the species (acidophilus), and the strain (Rosell-52). Different probiotic manufacturers use different strains, although these may be of the same species and genera; meaning that one acidophilus supplement is not equal to another acidophilus supplement. It is hence best to choose a probiotic supplement that uses robust, well researched strains.

Image explaining the genus, species and strain of a probiotic.

Many of our probiotic strain names include 'Rosell' as they originated from, and have been rigorously tested by, the leading probiotic firm, Institut Rosell. The example above, L. acidophilus NCFM®, is thought to be one of the most researched probiotic strains in the world. Find out more about Lactobacillus acidophilus NCFM®.

For further clarification on the difference between a genus, a species and a strain, please see the relevant terms in our glossary, or read 'The Strain Myth'.

Viable, effective strains

As well as selecting the optimum probiotic strains to target your personal health needs, it is important to consider the viability and efficacy of the probiotic strains themselves. In order to be an effective probiotic, the strains must be alive at the time of consumption, and must survive the stomach acidity and bile salts in order to reach the intestines. It is furthermore important that the probiotic strains are capable of adhering to the gut wall lining, so that they can in turn multiply and colonise the gut with good bacteria. The OptiBac Probiotics strains undergo numerous in-vitro tests documenting their viability at room temperature, their ability to survive the acidic stomach environment and bile salts, and their adhesion capabilities inside the gut.

Featured OptiBac Probiotics Strains

Lactobacillus acidophilus NCFM® can be found in our 'For every day EXTRA Strength' and 'For every day MAX' supplements. This particular strain is the most well-researched L. acidophilus in the world, with over 45 clinical trials covering a number of different health conditions, such as IBS and immune function support. NCFM stands for the 'North Carolina Food Microbiology' research laboratory, where it was first identified in the 1970s.

Bfidobacterium lactis BB-12® is the sole probiotic strain found in our 'Bifidobacteria & fibre' supplement. The B. lactis BB-12® strain is likely the world's most well-researched strain of the entire Bifidobacteria genus. It is notable for its ability to support digestion and gut motility, and is particularly well-researched for supporting health in those constipation. It has been trialled and shown to help aid bowel regularity amongst different populations, including in pregnant women, children and the elderly. Bifidobacterium lactis BB-12 has also been shown to support the immune system in a number of clinical trials.

B. lactis BB-12 as seen under microscopic inspection

Lactobacillus reuteri RC-14® & Lactobacillus rhamnosus GR-1® is a very unique combination of strains, in our 'For women' supplement, that have been found to support health in women with intimate health conditions such as thrush, cystitis, and bacterial vaginosis (BV). This combination of strains (the two have mostly been trialled as a pair) has over 30 years of clinical research, in more than 26 clinical trials including over 2,500 women.

Bifidobacterium infantis Rosell-33. This strain has been scientifically demonstrated to inhibit the adhesion of harmful strains of E. coli in the gastrointestinal tract, thereby supporting a healthier immune system in infants and children. Unlike in adults, an infant’s intestinal microbiota is susceptible to many changes, and this delicate balance between beneficial (probiotic) and pathogenic bacteria in a child’s gut contributes to their overall health and immunity. Unlike L. acidophilus, B. infantis mainly resides in the large intestine or colon. Bifidobacterium infantis Rosell-33 is one of the key ingredients in For babies & children.

Microscopic image of two B. infantis Rosell-33 cells

Saccharomyces boulardii is an internationally acclaimed probiotic yeast that works in a very different manner to our other strains. Saccharomyces boulardii is actually transient, and has undergone rigorous clinical research to demonstrate is ability to bind to and flush out pathogenic bacteria such as E. coli and Salmonella, naturally working against diarrhoea. Saccharomyces boulardii has also shown to have strong anti-inflammatory properties and to help prevent fungal overgrowth from yeasts such as Candida albicans.

Under the microscope: S. boulardii cells are naturally much larger than other microbes

Lactobacillus rhamnosus Rosell-11 & Lactobacillus acidophilus Rosell-52 is an incredibly well researched combination of strains, which is found in our 'For those on antibiotics' supplement. This combination of probiotics has over 31 clinical trials to back it up, with the majority of these focused on antibiotic-associated side effects. This specific duo of strains has been shown to help reduce the risk of antibiotic associated side effects during and after treatment, even when taken at the same time as antibiotic medication.


In conclusion, it is very important to look at probiotics on a strain-specific level, rather than only the genus and species of microorganism in question. To find out more about the OptiBac Probiotics range, take a look at the shop, or our recent blog post, 'Want the Best Probiotics? 5 Reasons we're the Best.'



  • What's the best probiotic regime for SIBO?

    What dosages?


  • Response from OptiBac Probiotics

    Dear Deep,
    One of our naturopaths will e-mail you regarding your question.

    Kind Regards,

  • A perfect detailed yet succinct reference for me to use when advising customers in the shop I work in! Thank you :)

  • Hi, can you tell me what the "NCFM" as the strain stands for? Also, I've heard that the best strain is DDS-1. I'd love your opinion on that please. Also, to what percentage in tests are your strains acid and bile resistant, ie. >90% for example? Many thanks.

  • Response from OptiBac Probiotics

    Dear Sam

    Thanks for your comment.

    Unfortunately I am not in a position to comment on other strains as I do not have access to their studies. I can however inform you that NCFM stands for North Carolina Food Microbiology as the strain was first isolated and registered at North Carolina University in the USA, and it is probably one of the most clinically trialled strains of probiotic bacteria in the world. You can read more about it <a href="https://www.optibacprobiotics.co.uk/resource-centre/faq/category-general-faqs/10-what-is-acidophilus-and-where-to-find-it.html">here</a>;

    At OptiBac Probiotics we focus on <a href="https://www.optibacprobiotics.co.uk/resource-centre/faq/category-general-faqs/12-are-all-types-strains-of-friendly-bacteria-the-same.html">specific strains</a> for different health conditions, and Lactobacillus acidophilus NCFM has been clinically trialled in a huge amount of studies, for its specific benefits for IBS, health in the elderly and pollen allergies.

    Regarding resistance to bile and acidity, the strains in the OptiBac Probiotics range were developed to survive gastric acidity above (i.e. more neutral than) pH 3. In-vitro trials on our probiotic strains show a 95 - 100% survival rate through gastric acidity at this pH. Research from microbiologists shows that at mealtimes (and especially breakfast time) the stomach's gastric acidity is naturally at pH 4 or above. If you would like to read more about this please <a href="https://www.optibacprobiotics.co.uk/resource-centre/faq/category-general-faqs/13-at-what-time-should-i-take-probiotics.html ">click here</a>

    Kind regards,

    In-house nutritional therapist.

  • Hi,

    I have IgA Immune disorder and was wondering what specific strain of probiotics should I be taking.


  • @ AL
    Thank you for your interesting question regarding the use of live cultures by sufferers of IgA immune disorders.
    I am going to request that my colleague Megan emails you directly about this complex issue.

  • what would be the best probiotic strains to take after an operation for an infection around the brain and while still on heavy antibiotics? Is this advisable?


  • Dear Maureen,

    Thank you for your question. Generally speaking probiotics are one of the safest food supplements available on the market, but for a very small percentage of our customers, notably those who have had major surgery with open wounds, or who are very ill in hospital, probiotics are not advised or are to be used only with the agreement of your doctor.

    For more safety information, please see our page ‘When should I NOT take probiotics?

    Many of the situations listed in this safety information are very prudent and anticipating the worst case scenario. Many people who have the health conditions listed in the safety section have in fact taken probiotics with no negative effects, but there have been very rare incidences where the person has experienced a negative effect and we cannot be sure if the probiotics were the cause of the deterioration or not. This is why we must always err on the side of caution to minimise all potential risks to the individual.

    Many probiotic companies don’t even make the consumer aware of cautions! This goes to show how very infrequently they arise. We just like to be ultra careful and transparent, so that if there happens to be any reason for hesitation then you and your doctor can make an informed decision.

    I hope that this answers your question, but if you require any further information, please do not hesitate to contact me on [email protected]

    Wishing you the best of health,


  • Al
    I think I have finally convinced a friend to start on a strain but we are so lost & don't know were to start. She has had in the pass c diff but for now the major problems are IBS-D, Addisons Disease & Ulcerative Colitis. She has bloating & cramping so we need to stay away from any strains that induce bloating & cramping if possible.
    Many thanks, Dave

  • Truly, not all probiotics are helpful for all kinds of illnesses. Primarily, probiotics function to help flourish our gut with the good bacteria that it needs. However, there are specific bacteria strains needed for specific ailments.

  • What strain would be best for excess acid. I am on 40mg of omeprozole and would like to get off it.

  • @ Jeff,

    Probiotics are primarily active in the intestines rather than the stomach; however, sometimes stomach issues can be aggravated by intestinal dysbiosis.

    If this is the case, then taking a good broad-strain probiotic may prove to be helpful.

    For more information on this condition, which may arise due to many different factors, and how probiotics might help, see our recent blog: 'Acid reflux - why to consider probiotics'

    Wishing you the best of health,


  • I have severe psoriasis and was wondering which of your products would help me most?

  • Hi Lorraine,

    Thanks for your question.
    It's interesting that you're looking for a probiotic to help support skin conditions such as psoriasis and eczema.

    We keep an eye on all of the latest research that explores potential applications for probiotic bacteria, and the link to gut health in many, apparently unrelated health conditions, is becoming more well-documented with each passing year. Skin health in particular seems to be linked to the composition of gut bacteria, and we have written various articles and information pages which explain why this might be.
    Click on the following links to learn a little more about why probiotics could help improve skin conditions, and which to use:
    'Probiotics and eczema' - Dr. Georges Mouton.

    FAQ 'Do probiotics help with eczema?'

    'OptiBac Probiotics for Inflammation'

    I hope this information helps, but do feel free to contact me directly on [email protected] should you wish to discuss your individual probiotic needs in more detail.

    Warm wishes,


  • Hi,
    Do you have information on the BB06 strain?

  • Response from OptiBac Probiotics

    Dear Cza,

    Thank you for your query.
    Unfortunately, Bifidobacterium bifidum Bb-06 is not a strain that we carry within our range, and I am not in a position to comment on other strains as I do not have access to their studies.

    Kind regards,

    Nutritional Advisor
    OptiBac Probiotics

  • I get plenty of probiotics from the usual food sources, i.e. yoghurt, probiotics from the health food store (those sweet "yogurt-like" probiotics that come in little plastic wide-mouthed bottles). I would like to take probiotics that are naturally found in human body. What probiotics do you sell that are only found in the human body? Thank you!

  • Response from OptiBac Probiotics

    Hi Ecira,

    Thanks for your question.

    Firstly, whilst its great to include a wide variety of fermented foods in the diet, you need to be careful that those you choose don't contain lots of sugar or sweeteners, and also you need to consider that often the strains of bacteria in these type of foods are 'transient' in nature, meaning that they're not going to colonise in the digestive tract for any length of time.
    Take a look at our FAQs on this subject here:
    'Why consider OptiBac Supplements over natural bio yogurt?
    'Why consider OptiBac Probiotics over probiotic yoghurt drinks?'

    There are a lot misconceptions and myths circulating about this subject, and how we can obtain the right strains of probiotics for our needs, and whether its possible to do this by diet alone - see our Food myths information page in our new 'Probiotic Myths - Busted!' section

    I can certainly advise you which 'human strains' we carry in our range - you'll find them all listed on 'What are Human Strains?' page: https://www.optibacprobiotics.co.uk/live-cultures/articles/what-are-human-strains

    Whilst our 'For every day EXTRA Strength' product does contain almost all 'human strains' of bacteria, I'd like to explain a little more about what you should think about when choosing the right live cultures supplement for your needs. The key consideration you should have is whether you are choosing the correct strain of bacteria to help support your individual health condition.

    Different strains have bacteria have totally different attributes, and for more about this, see the 'Cure-All' Myth in the 'Myth-busting section https://www.optibacprobiotics.co.uk/live-cultures/probiotic-myths/cure-all-myth

    Our website offers a wealth of information about our products to help you make an informed decision, but you're also welcome to contact us directly using our Contact Form if you'd like more advice about which probiotic is best for you.

    Kind regards,

    Nutritional Advisor
    OptiBac Probiotics

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