Live cultures
Lactobacilli, bifidobacteria, CFU and strains: what the label of a live-culture supplement says, how to store it and how to choose.
This substance has no health claim authorised in the European Union. So we describe what it is and how it is taken, but do not say what it does in the body.
What they are
These are supplements with live micro-organisms — most often lactic acid bacteria of the genera Lactobacillus (many now renamed, e.g. Lactiplantibacillus) and Bifidobacterium, and the yeast Saccharomyces boulardii. The same cultures live in kefir, yoghurt and sauerkraut.
In everyday speech they are called probiotics. In the European Union the word "probiotic" on a product counts as a health claim in itself, and live cultures in supplements have no authorised claim. So we describe the contents and the choice, but do not write what they do for the gut or immunity.
How to read the label
A strain is the full name of a particular culture: genus, species and code, e.g. Lactobacillus rhamnosus GG. Strains of one species differ, so good makers state the strain code.
CFU (colony-forming units) is the number of living cells, usually 1–50 billion per serving. It matters whether the count is stated at manufacture or guaranteed to the end of the shelf life: the second is more honest.
How they are taken and stored
Capsules are taken as the pack directs, usually once a day, often with a meal. Some products need the fridge — the pack says so; others are stable at room temperature. Enteric-coated capsules are designed to pass the stomach. People with weakened immunity or serious illness should ask a doctor first.
Frequently asked questions
Why don't you call them probiotics?
In the EU the word "probiotic" on a product counts as a health claim, and these cultures have no authorised claim. So we use a neutral name.
What is CFU?
Colony-forming units — the number of live cells per serving. Look for a count guaranteed to the end of the shelf life.
Do they need refrigerating?
It depends on the product: check the pack. Many modern capsules are stable at room temperature.
Can live cultures be taken with antibiotics?
Discuss it with a doctor; they are often taken at different times.
Are there cultures in ordinary food?
Yes, in kefir, live yoghurt, sauerkraut and other fermented foods.
Digestion & probiotics in the shop
