Prebiotics & Probiotics

Our gut's diverse ecosystem is made up of trillions of different bacteria.

The bacteria that are present in our gut benefit far beyond just the gut itself, playing a role in our immune system and even our mental health. We’ve all heard of the benefit of prebiotics and probiotics in our diets, but do we really understand what these are and the differences between them?

With thousands of news articles, blogs and opinions, it can be difficult to pinpoint exact definitions and find reliable information sources. To tackle this tricky subject, we’ve put together an ‘all you need to know’ guide about probiotics and probiotics.


A good way to explain prebiotics is by thinking of them as fertilisers in our gardens, to help feed and grow all our plants. By adding a prebiotic to our diet, we can similarly feed and help our gut bacteria grow strong to benefit our overall ecosystem.

Many plant foods contain different types of prebiotics. Artichokes, asparagus, bananas, berries, tomatoes, garlic, onions, legumes, green vegetables and wholegrain cereals are some examples. Prebiotics can also be manufactured artificially and added into foods or supplements.


In Europe, probiotics are considered food supplements and such products cannot be labelled as probiotics at present. Research has shown that some probiotics can help to improve diarrhoea caused by infection or by treatment with antibiotics. Probiotics might also relieve some digestive symptoms. At present, there isn’t enough evidence to support other health claims or probiotics, or the evidence for their usefulness is inconclusive.

Probiotics are generally considered safe for people with a normal immune system. If you want to try a probiotics for a health problem, you should ask your GP or dietitian for advice. The specific type of bacteria, dose and composition of the probiotic are important.

NHS Website – Probiotics

British Dietetic Association – Probiotics

More information: