Should patients be taking probiotics and prebiotics?

What's the difference between prebiotics and probiotics?

Prebiotics

Prebiotics are foods which provide direct nutrition for the healthy bacteria and other microbes in the gut (colon). These foods are usually high in fibre and help to support a healthy microbiome (bacteria) and other microbes in the gut.

Probiotics

Probiotics are live microorganisms added to food or supplements. They can also naturally occur in some fermented foods like tempeh, miso, kefir, boza, kimchi, and sauerkraut.

If taken in a large enough quantity they can change the microbiome in the gut and improve the amount of  'good' bacteria and other microbes (microbiome).  

Many food products claim to have health benefits. However, there is not strong enough evidence for health professionals to recommend specific foods or supplements. They are generally thought to be safe and can be used in moderation as part of a healthy diet unless immunocompromised.

Important safety note

Probiotics are not recommended for patients who have a weakened immune system or who are taking steroid medications (corticosteroid therapy).

What is the evidence for using probiotics during COVID-19 recovery?

Researchers believe that changing the balance of the microbiome in our gut and lungs might help prevent or treat COVID-19 infection. This is because certain beneficial bacteria (probiotics) and the fibres that feed them (prebiotics) can support the immune system.

Changes in gut and lung microbiome were seen in people with severe COVID-19 with a suggestion of a gut-lung connection (Aan et al., 2022).  

Trying to change the microbiome using probiotics, prebiotics, and related treatments (synbiotics and postbiotics) may be a promising supportive approach for improving the health of people with COVID-19 infection and symptoms. However, there are too few studies to be confident about the role gut microbiome, probiotics, prebiotics and related treatment in COVID-19 infection and recovery. 

A summary of the review by Xavier-Santos et al., (2022) on probiotics in COVID-19 states that there are only a few studies which have tested using probiotics in people with COVID-19. A few early clinical studies have tested giving probiotics to people with COVID-19 with limited research showing that probiotics may:

• Reduce how long the illness lasts
• Less severe symptoms, such as fatigue (tiredness), loss of smell, difficulty breathing, nausea and vomiting. other digestive problems

The evidence for use in preventing or recovery from COVID-19 is weak and more research is needed to understand any benefits or risks.

What does this mean for patients?

There is currently not enough evidence to recommend using probiotics for COVID-19 recovery. 

Research is ongoing and adding to the evidence for clinical practice. This may mean we can make recommendations in the future about how much and what type of probiotic or similar treatment is helpful in COVID-19 infection and recovery.

Probiotics should not be used by anyone who is immunocompromised, including those taking corticosteroids.

Want to know more about supplements, pre- and probiotics?

• You can watch our Q&A session with topic experts where they discuss the use of supplements.
• Read the British Dietetic Association's Guide to pre- and probiotics.

Want to know more about nutrition and COVID-19? 

Listen to or watch our podcasts about:

• Diet and COVID-19
• Dietary advice and symptoms, malnutrition, antihistamine diets 
• Anti-inflammatory diets with a discussion about the Mediterranean diet in more detail
• Links between food and COVID-19 symptoms which explains how to monitor your symptoms and possible dietary changes you could make