Probiotic supplements vary far more than the front of the pack suggests. Two products with similar names can contain different strains, very different counts and packaging that protects the cultures to a very different degree. The steps below work for any product, from capsules to gummies, and none of them needs specialist knowledge.
1. Be clear about why you are considering one
Start by noting why you want to try a probiotic, as that helps you decide which details on the label matter most to you. Bear in mind that no health claims are currently authorised for probiotics in Great Britain, so a responsible label will not promise to treat or fix anything. If you have a specific health concern, a pharmacist or GP is the right person to ask before you buy.
2. Check the full strain names
A probiotic label should name each culture by genus and species, and ideally by a strain code made of letters or numbers, such as Lacticaseibacillus rhamnosus followed by its code. The code matters because research on one strain does not automatically apply to another strain of the same species. A label that lists only "lactobacillus" or "good bacteria" tells you much less. Our probiotic strain guide explains the main groups you will see.
3. Check the CFU count and when it applies
CFU stands for colony forming units, an estimate of the live microbes in each serving. Look for the count per daily serving, then check whether the label says it holds until the best-before date or only at the time of manufacture. A count stated to the end of shelf life is the more useful figure, and a higher number is not automatically better. Our guide to understanding CFU counts explains how to compare them fairly.
4. Choose a format you will use
Capsules, powders and sachets, gummies, liquid drops and chewables are all available, and the right one is mostly about what you find easy to take each day. Format also affects which strains can be used, because the heat involved in making gummies limits them mainly to spore-forming species such as Bacillus coagulans. You can compare the options side by side on our probiotic types page.
5. Check dietary needs and allergens
Read the ingredients list for allergens, which must be emphasised, and check whether the capsule shell is gelatine or plant-based if you are vegetarian or vegan. Some cultures are grown on dairy-based media, so look for a clear statement if you avoid milk. Gummies may use gelatine or pectin and often contain sugar or polyols. Some products also add prebiotic fibres such as inulin, FOS or GOS, which some people find cause wind.
6. Check storage and packaging
Live cultures decline faster when exposed to heat, moisture and oxygen, so packaging does real work. Foil blisters and individual sachets keep each dose sealed, while bottles and tubs work better with a desiccant to absorb moisture. Check whether the product needs refrigeration, especially after opening, and make sure that suits your routine. Our storage and shelf life guide goes into more detail.
7. Read the whole label
A probiotic sold in Great Britain is a food supplement, so its label must carry the words "food supplement", the recommended daily dose and a warning not to exceed it. You should also find a best-before date, storage conditions, a batch code and the name and address of the business responsible. Follow the label for how much to take, and see our guide on how to read a probiotic label for each item in turn.
8. Avoid red flags when choosing a probiotic
Any one of the following is a reason to look more closely at a product, and several together suggest choosing a different one.
- Claims that the product treats, cures or prevents a condition
- No strain names, or only vague terms such as "good bacteria"
- A CFU count with no indication of when it applies
- No storage instructions, batch code or business address
- Packaging that is damaged, unsealed or past its best-before date
Our page on how to judge probiotic quality covers the positive signs of a carefully made product.
9. Speak to a pharmacist when it is relevant
Probiotics are generally considered safe for healthy adults, and some people notice mild wind or bloating at first. If you are pregnant or breastfeeding, have a weakened immune system or a serious illness, or take medication, including antibiotics, speak to a pharmacist or GP before you start. The same applies if you are buying for a baby or child. For a general question about a label, you can also ask us a question.