Live Culture Supplements Explained: CFU, Strains and Labels

Supplements containing live bacterial cultures can be confusing to compare. Labels are full of large numbers, Latin names and codes. This guide explains what those terms mean so you can read a label with confidence. It is about understanding the label, not about health effects: in the UK, no health claims are authorised for live bacterial cultures, so we do not make any.

What is in a live culture supplement?

These products contain one or more types of live bacteria, usually from groups such as Lactobacillus (several of which now have new genus names) and Bifidobacterium. Some products also contain a fibre such as inulin.

What does CFU mean?

CFU stands for colony forming units. It is a measure of how many live, viable bacterial cells a product contains. Labels usually state CFU per capsule or per daily serving, for example 20 billion CFU.

At manufacture or at end of shelf life?

This is one of the most important details. Live cultures naturally decline over time, so a label should say when the CFU figure applies:

• At time of manufacture: the count when the product was made.
• At end of shelf life: the minimum count guaranteed until the best before date.

The two products described below state CFU at time of manufacture.

Is a higher CFU better?

Not automatically. A bigger number is not a health claim, and different products are not directly comparable unless the strains are the same. Look at the whole label, not just the headline figure.

Understanding strain names

A full strain name has three parts:

1. Genus, for example Bifidobacterium.
2. Species, for example animalis subsp. lactis.
3. Strain code, a combination of letters and numbers that identifies one specific strain.

Different strains of the same species can behave differently, which is why a full name with a strain code is more informative than a species name alone. A good label lists every strain by its full name and code.

What is inulin?

Inulin is a type of dietary fibre found naturally in plants such as chicory root. Some products combine live cultures with inulin. If a label includes inulin, it should state how much is in each capsule.

Storage

Always follow the storage instructions on the label. Some products need refrigeration, while others are designed to be stored in a cool, dry place away from direct sunlight and moisture. Keep the container tightly closed.

A label checklist

• CFU per capsule and per daily serving
• Whether CFU is stated at manufacture or at end of shelf life
• Every strain listed by genus, species and strain code
• Any added fibre, such as inulin, and the amount
• Capsule type, for example vegan HPMC
• Storage instructions and suggested use

Our live culture products

Our 20 billion CFU live culture capsules provide 20 billion CFU per capsule at time of manufacture, from six named strains with their strain codes declared on the label, in a 333 mg blend. The suggested use is one capsule daily, and no fridge is needed.

Our 40 billion CFU live cultures with inulin provide 40 billion CFU per capsule at time of manufacture from six named strains, together with 350 mg of organic chicory root inulin powder. Both use vegan HPMC capsules. You can see the full range in our Gut and Digestion collection.

Frequently asked questions

What does 20 billion CFU mean?

It means the product contains 20 billion colony forming units, a measure of live bacterial cells, per capsule or serving, at the point stated on the label.

Why do strain codes matter?

Because different strains within the same species can differ. The strain code identifies exactly which strain is in the product.

Do live culture capsules need to be refrigerated?

It depends on the product. Always follow the storage instructions on the label.

Are there authorised health claims for live cultures?

No. In the UK, no health claims are authorised for live bacterial cultures.

Important information

Food supplements should not replace a varied, balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose stated on the label. Not intended for anyone under 18. If you are pregnant, breastfeeding, taking any medication, have a weakened immune system or are under medical supervision, speak to your doctor or pharmacist before taking any food supplement. Keep out of reach of children.