How To Choose The Best Probiotic Supplement

Confused about which are the best probiotic supplements? We can help you to decide.

Microbiologist, Dr. Kate Stephens, and gut health expert, Nutritional Therapist Kerry Beeson, answer the Top 5 Questions our Nutrition Team are asked by confused customers. Let us help you to choose the perfect probiotic supplement for your needs:

  1. You don’t need probiotic supplements with lots of strains
  2. High strength does not always mean high quality
  3. Liquid probiotic supplements are not more effective than capsules, powders, or gummies
  4. Choose the probiotic supplement that is right for your individual needs
  5. It’s important to choose a trusted, expert brand 

Jump straight to the end if you have a question that's not answered here or are just not sure where to start?


1. You don’t need probiotic supplements with lots of strains

It’s quality not quantity that matters when choosing a live cultures supplement. You don’t need to keep switching brands to try lots of different products or choose multi-strain probiotic supplements containing large numbers of different friendly bacteria. Many renowned probiotic strains, such as Bifidobacteria lactis BB-12® or Saccharomyces boulardii,1,2, are typically researched alone. So just choose a probiotic supplement containing high-quality strains, proven to reach the gut or vaginal flora, and researched in for the health concerns you wish to support, such as digestion3, immune health4, or mood and wellbeing5. If you buy from expert companies, the strains will always be shown on the packaging, not just the species, so you can make an informed choice.

probiotic strain

2. High strength does not always mean high quality

In the same way that you don’t need to look for probiotic supplements with lots of strains, you don’t always need one with a high number of billions. You will pay more for these high-strength supplements, and you may not need all those extra billions6! Live cultures specialists use the same number of billions used in the supporting clinical trials, so you never pay for more than you need. It’s better to choose a supplement containing high quality probiotic strains researched for your individual needs rather than a generic high-strength formula. 

3. Liquid probiotic supplements are not more effective than capsules, powders, or gummies

This is a common misconception. Live cultures supplements come in capsules, sachets, liquids, and gummies, which can be very confusing! Many people think that liquids are absorbed better or reach the gut more quickly. But this is not the case - if you choose a high-quality, well-researched probiotic supplement, you can be confident that the friendly bacteria strains are tested to reach the gut6, whether they're in capsules, liquids, or any other format. Probiotic specialists only use highly researched live cultures, so you can opt for the format which suits you best.

4. Choose the probiotic supplement that is right for your individual needs

Not all friendly bacteria strains have the same properties, so it’s important to choose a probiotic supplement containing strains researched for your individual requirements. Friendly bacteria specialists always include the strain names in the ingredients. Once you know the strain name, you can see what it’s been researched for. For example:

  • General digestive health: the Every Day supplement contains strains of Lactobacillus and Bifidobacteria naturally found in the digestive tract, and proven in over 20 years of research to reach the gut alive6
  • For babies: Bifidobacterium breve M-16V® has been widely researched in babies7 – find this strain in Baby Drops
  • For children: The strain in Kids Gummies, Bacillus coagulans Unique IS-2, is one of the one of the most researched strains of Bacillus in children8,9,10
  • For pregnancy: The strains in Pregnancy,  such as Lactobacillus rhamnosus HN0018, have been widely researched in pregnant and breastfeeding women11
  • Vaginal health: Lactobacillus rhamnosus GR-1® and Lactobacillus reuteri RC-14® are proven to reach the vaginal flora13 – find these strains in For Women

For free advice about how to use the rest of our range, contact our Nutrition Team.

probiotic capsule

5. It’s important to choose a trusted, expert brand

With so many different options available in the UK, deciding which is the best probiotic supplement can be very confusing. Ideally, look for a trusted specialist brand with products backed by sound science. At Optibac Probiotics we have decades of experience and specialise only in live cultures supplements. We always use probiotic strains backed by credible science and prioritise natural ingredients.

If you now feel fully informed, go ahead and choose your ideal probiotic supplement in our US Shop.

Still not sure where to start?

If you’re still confused about which is the best probiotic supplement for you, and don't have any specific health concerns to support, then why not just start with this daily product for all-round digestive support and see how you feel:

Every Day

  • 6 high quality probiotic strains.
  • 5 billion CFU guaranteed per daily dose.
  • Well researched & proven to survive to reach the gut alive.
  • Natural all-round daily support for gut health and general wellbeing
  • Complements your natural microbiome.
  • With FOS fibres to help support your gut Bifidobacteria.
  • Easy to take capsule, with no nasty additives.
  • Great value for money at $17.99 for 1 month's supply.

Try taking this with your breakfast every day and let us know how you get on! Or look at this FAQ to find out more about our other daily probiotic supplements.

Alternatively, if you need further guidance, contact our team of experts for free advice.


  1. Eskesen et al. (2015) Effect of the probiotic strain Bifidobacterium animalis subsp. lactis BB-12®, on defecation frequency in healthy subjects with low defecation frequency and abdominal discomfort: a randomised, double-blind, placebo-controlled, parallel-group trial. Br J Nutr; 114, 10: 1638-46.
  2. McFarland (2010) Systematic review and meta-analysis of Saccharomyces boulardii in adult patients. World J Gastroenterol; 16, 18: 2202-22
  3. Satish Kumar L, Pugalenthi L, Ahmad M, et al. (April 18, 2022) Probiotics in Irritable Bowel Syndrome: A Review of Their Therapeutic Role. Cureus 14(4): e24240. doi:10.7759/cureus.24240 
  4. Jespersen L. et al., (2015), ‘Effect of Lactobacillus paracasei subsp. paracasei, L. casei 431® on immune response to influenza vaccination and upper respiratory tract infections in healthy adult volunteers: a randomized, double- blind, placebo-controlled, parallel-group study’. Am.J.Clin.Nutr., 101:1188-1196.
  5. Messaoudi M. et al., (2011), ‘Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and human subjects’. British Journal of Nutrition, 105(5):755.
  6. Nagulesapillai, V. et al (2015) Detection and quantification of strain specific probiotics in clinical faecal samples of healthy adults on antibiotic treatment by quantitative PCR.
  7. Patole et al. (2014). Effect of Bifidobacterium breve M-16V® supplementation on faecal Bifidobacteria in preterm neonates- a randomised double blind placebo controlled trial . PLoS one, 9 (3): e89511.
  8. Saneian, H. et al. (2015) ‘Synbiotic containing Bacillus coagulans and fructo-oligosaccharides for functional abdominal pain in children’, Gastroenterol Hepatol Bed Bench, 8(1), pp. 56–65.
  9. Sudha, M. and Arunasree, K. (2015) ‘ANTI-INFLAMMATORY AND IMMUNOMODULATORY EFFECTS OF BACILLUS COAGULANS UNIQUE IS2’, International Journal of Probiotics & Prebiotics, 10(1), pp. 31–36.
  10. Sudha, M. R. et al. (2018) ‘Efficacy of Bacillus coagulans Unique IS2 in treatment of irritable bowel syndrome in children: a double blind, randomised placebo-controlled study’, Beneficial Microbes, 9(4), pp. 563–572. doi: 10.3920/BM2017.0129.
  11. Slykerman R et al. (2017). Effect of Lactobacillus rhamnosus HN001 in pregnancy on postpartum symptoms of depression and anxiety: a randomised double blind placebo controlled trial . EBioMedicine, 24, 159-165.
  12. Evans M. et al., (2016), ‘Effectiveness of Lactobacillus helveticus and Lactobacillus rhamnosus for the management of antibiotic-associated diarrhoea in healthy adults: a randomised, double-blind, placebo-controlled trial’. British Journal of Nutrition, 116(1):94-103. doi: 10.1017/S0007114516001665. Epub 2016 May 12.
  13. Morelli L. et al., (2004), ‘Utilization of the intestinal tract as a delivery system for urogenital probiotics’. J. Clin. Gastroenterol., 38(6 Suppl): S107-10.