THE ALPHA01 GUIDE LIVE CULTURES
Saccharomyces
Boulardii Capsules: What Does 5 Billion CFU Mean?
One named yeast. One daily capsule.
A clearer look at the count on the label.
You already know this yeast’s family. Saccharomyces cerevisiae is the yeast that makes bread rise 7 and ferments beer and wine 8, and Saccharomyces boulardii is a close relative with a story of its own, first found on lychee and mangosteen fruit in the 1920s 6. On our pouch it is printed simply as a yeast micro-organism, with one number beside it: 5 billion CFU in a single capsule 4.
Choosing a live cultures supplement can feel confusing, especially when one pouch lists twenty bacteria and another names a single yeast. This guide explains what the 5 billion on our label counts, where this yeast was first found, how to take one capsule a day and which of our pouches fits your routine.
Saccharomyces boulardii at a glance
- What it is: a food supplement with one named yeast, Saccharomyces boulardii, printed on the pouch as a yeast micro-organism 4.
- What 5 billion means: the count of live cells, in CFU, in one capsule, and one capsule is the whole daily serving.
- How to take it: one capsule a day with water, 90 capsules to a pouch.
- Ingredients: the yeast, a hypromellose capsule shell, rice starch and safflower oil.
- Price: £8.99 for 90 days, about 10p a day.
- Who it suits: you, if you want one named live yeast in a single capsule a day, with the count printed on the pouch.
ONE NAMED YEAST
Saccharomyces Boulardii
5 billion CFU in one daily capsule.
A single yeast micro-organism in a plant-derived shell.
01 / MEET THE MICRO-ORGANISM
What is Saccharomyces boulardii? A yeast, not a bacterium
When you think of live cultures, you probably picture bacteria. The NHS describes them as “live bacteria and yeasts” that are “usually added to yoghurts or taken as food supplements” 1, and Saccharomyces boulardii belongs to the smaller group: it is a yeast.
That’s why the front of our pouch calls it a yeast micro-organism 4. Our Bio Cultures Complex lists twenty names on its panel, every one of them a bacterium. This pouch lists just one: the yeast.
Is Saccharomyces boulardii the same as brewer’s yeast?
Not quite, but it is a very close relation. The bread yeast, Saccharomyces cerevisiae, earned its place in the ancient art of bread making by turning carbohydrates into carbon dioxide quickly 7, and the same species is used for beer and wine 8. When scientists compared the two side by side, they found Saccharomyces boulardii “genetically very close or nearly identical to S. cerevisiae“ 5.
Despite the family resemblance, it has a character of its own. The same comparison found it behaved very differently in its growth and in how it coped with temperature 5. Once described as a species in its own right, it is now listed as a synonym of S. cerevisiae, a variant of the same species, and the reference culture that yeast specialists study carries the main genetic features of a wine yeast 9.
Where Saccharomyces boulardii was first found: lychee and mangosteen
The second half of the name belongs to a person: Henri Boulard. He was the French scientist who first isolated Saccharomyces boulardii from lychee and mangosteen fruit in the 1920s 6.
02 / READ THE LABEL
Saccharomyces boulardii 5 billion CFU: what the label counts
Five billion of what, exactly? The small print on our panel answers it: CFU = Colony Forming Units. Think of it as a headcount of the live cells that are able to grow, which is how you count something that is alive.
Nutritional Information
Serving Size: 1 Capsule
Servings Per Container: 90
| Ingredient | Amount per Serving | %NRV* |
|---|---|---|
| Saccharomyces boulardii | 5 billion CFU | ** |
* Nutrient Reference Value
** No NRV established
CFU = Colony Forming Units
capsule a day
billion CFU
Saccharomyces Boulardii 5 Billion CFU, nutrition panel and price 4
The serving size is one capsule, so the 5 billion CFU on the front of the pouch is the count the panel declares for your one daily capsule 4. In the %NRV column you’ll see two asterisks, and the footnote explains them: No NRV established. There is no daily reference value for a live culture, so no percentage is given.
What else is in Saccharomyces boulardii capsules?
The ingredients list is short: the yeast itself, a plant-derived hypromellose capsule shell, rice starch and safflower oil 4. There is no gelatin, and the storage line asks for a cool, dry place out of direct sunlight, with no mention of a fridge.
03 / FIND YOUR ROUTINE
Saccharomyces boulardii or a bio cultures complex: which fits your routine?
Each of our live cultures pouches makes for a simple daily routine, so the choice comes down to one question: would you rather have a single yeast, or a blend of bacteria?
A SINGLE YEAST
Saccharomyces boulardii capsules: one yeast, one capsule a day
Want one named culture and the simplest routine? Our Saccharomyces Boulardii 5 Billion CFU capsules are one a day with water, and each pouch of 90 lasts 90 days at about 10p a day.
A BLEND OF BACTERIA
Bio Cultures Complex: twenty live cultures in two capsules
Prefer a blend? Our Bio Cultures Complex 60 Billion capsules list twenty named bacteria and give 60 billion CFU in two capsules, for about 33p a day. The same twenty come at a higher count in our 100 Billion capsules, for about 50p a day.
Curious who the twenty names are? Our guide, Bio Cultures Complex: 60 Billion or 100 Billion CFU?, explains the main groups on the panel.
All three pouches sit in our Bio Cultures range, and you’ll find them in Live Cultures too.
04 / COMPARE THE RANGE
Saccharomyces boulardii vs bio cultures complex: how the labels compare
The table puts our three live cultures pouches side by side: what each label names, the count in a serving and the cost per day. Prices are correct at the time of writing.
| Product | What the label declares | Routine & value |
|---|---|---|
1 capsule · 5 billion CFU of one yeast, Saccharomyces boulardii · hypromellose shell, rice starch and safflower oil | Choose if you want one named yeast in a single capsule a day · vegan · 90 days · £8.99: about 10p a day | |
2 capsules · 60 billion CFU from a blend of 20 named bacteria · with inulin · hypromellose shell | Choose if you want twenty bacteria in one routine · vegan · 30 days · £9.99: about 33p a day | |
2 capsules · 100 billion CFU from the same 20 bacteria · with inulin · hypromellose shell | Choose if you want the same blend at a higher count · vegan · 30 days · £14.99: about 50p a day |
TWENTY NAMED BACTERIA
Bio Cultures Complex 60 Billion
60 billion CFU per two-capsule serving.
A blend of twenty named bacteria, with inulin.
THE SAME BLEND, A HIGHER COUNT
Bio Complex Cultures 100 Billion
100 billion CFU per two-capsule serving.
The same twenty named bacteria, with inulin.
05 / KEEP IT SIMPLE
How to take Saccharomyces boulardii
One daily capsule
The directions are simple: one capsule daily with water 4. The label doesn’t tie you to a time or a meal, so take it whenever it suits your day, and keep to one a day.
A cool, dry place
Store the pouch in a cool, dry place, out of direct sunlight and out of reach of young children. At one capsule a day, a pouch of 90 lasts about three months.
A SIMPLE DAILY ROUTINE
One yeast, one capsule, about 10p a day
If a straightforward routine suits you, it’s just one capsule a day: 5 billion CFU of Saccharomyces boulardii, and an £8.99 pouch of 90 lasts about three months.
SHOP SACCHAROMYCES BOULARDII06 / A LITTLE MORE CLARITY
Saccharomyces boulardii FAQs
What are the benefits of Saccharomyces boulardii?
UK rules authorise no health claim for Saccharomyces boulardii, so we list none 2. What our capsules do offer is practical: one named yeast, 5 billion CFU and one capsule a day, all printed on the label.
Is Saccharomyces boulardii a probiotic?
How do you pronounce Saccharomyces boulardii?
Say it sak-uh-roh-MY-seez boo-LAR-dee-eye. The second word, boulardii, comes from Henri Boulard, the scientist who first isolated the yeast 6. You’ll often see the name shortened to S. boulardii.
Does Saccharomyces boulardii need to be kept in the fridge?
Our label doesn’t ask for it. It says to store the pouch in a cool, dry place out of direct sunlight 4.
Are your Saccharomyces boulardii capsules vegan?
Yes. The capsule shell is hypromellose, a plant-derived material, and nothing on the ingredients list comes from an animal, so the capsules belong to our vegan range.
Can I take Saccharomyces boulardii every day?
Yes. The label is written for one capsule a day with water, so a pouch of 90 covers 90 days of that routine.
The capsules are not intended for children. If you are pregnant, breastfeeding, have a medical condition or take medication, the label asks you to check with a doctor before use, the same advice the NHS gives anyone with “an existing health condition or a weakened immune system” 1.
Can I take Saccharomyces boulardii with a bio cultures complex?
They are two separate products, and each label sets its own serving: one capsule a day for Saccharomyces boulardii, two for the Bio Cultures Complex. Whether you take one or both, follow the directions printed on each pouch.
THE BOTTOM LINE
So, one yeast or twenty live cultures?
Choose Saccharomyces Boulardii capsules if you want one named yeast: 5 billion CFU in a single daily capsule, at about 10p a day. Choose the Bio Cultures Complex 60 Billion capsules if you’d rather take a blend of twenty bacteria, two capsules a day at about 33p. You now know what the number on the front of the pouch means, which makes the choice a simple one.
GO TO THE SOURCE
Sources & references
Checked against the product labels and the GB Nutrition and Health Claims Register, October 2026.
- Probiotics – NHS. Accessed 2026-10-02. View source
- Department of Health and Social Care. Great Britain nutrition and health claims (NHC) register, GOV.UK (every Saccharomyces boulardii entry non-authorised). Accessed 2026-10-02. View source
- Department of Health and Social Care. Nutrition and health claims: guidance to compliance with Regulation (EC) 1924/2006, GOV.UK (the word ‘probiotic’ as an example of a health claim). Accessed 2026-10-02. View source
- Alpha01. Saccharomyces Boulardii 5 Billion CFU, 90 Capsules: pouch front, nutritional information panel, ingredients, suggested use, storage, caution and price; Bio Cultures Complex 60 Billion and Bio Complex Cultures 100 Billion labels and prices. Accessed 2026-10-02. View source
- Fietto JL, Araújo RS, Valadão FN, Fietto LG, Brandão RL, Neves MJ, Gomes FC, Nicoli JR, Castro IM. (2004). Molecular and physiological comparisons between Saccharomyces cerevisiae and Saccharomyces boulardii. Canadian Journal of Microbiology, 50(8):615-621 (cited for the genetic and growth comparison only). PubMed. View source
- Hossain MN, Afrin S, Humayun S, Ahmed MM, Saha BK. (2020). Identification and Growth Characterization of a Novel Strain of Saccharomyces boulardii Isolated From Soya Paste. Frontiers in Nutrition, 7:27 (cited only for who first isolated the yeast, from which fruit and when). PMC. View source
- Randez-Gil F, Córcoles-Sáez I, Prieto JA. (2013). Genetic and phenotypic characteristics of baker’s yeast: relevance to baking. Annual Review of Food Science and Technology, 4:191-214 (cited for bread making only). PubMed. View source
- Verstrepen KJ, Derdelinckx G, Verachtert H, Delvaux FR. (2003). Yeast flocculation: what brewers should know. Applied Microbiology and Biotechnology, 61(3):197-205 (cited for beer and wine only). PubMed. View source
- Pontes A, Hutzler M, Brito PH, Sampaio JP. (2020). Revisiting the Taxonomic Synonyms and Populations of Saccharomyces cerevisiae: Phylogeny, Phenotypes, Ecology and Domestication. Microorganisms, 8(6):903 (cited for the name and the reference culture only). PMC. View source
