Are psychobiotics the new frontier in gut health?

Psychobiotics are prebiotics and probiotics that can influence mental wellbeing. Here’s what you need to know.

The idea of eating our way to happiness sounds like an exciting notion, but a growing area of research into psychobiotics is investigating just that. 

We know probiotics are the good bacteria that nourish the gut, while prebiotics encourage growth of beneficial gut bacteria, but scientists are studying how they can also alter the mind – and the results are promising.

What are psychobiotics?

Probiotics are the live bacteria and yeasts found in yoghurt and other fermented foods, touted as good for your digestive system. 

Western Sydney University gastroenterologist Dr Vincent Ho says psychobiotics are probiotics studied for their potential impact on brain function and some brain-related conditions, including anxiety and depression. 

“Psychobiotics are live bacteria, that when you ingest them in a sufficient amount, can convey some health benefits, particularly for the brain,” Dr Ho says.

How can psychobiotics be used?

There’s already evidence some probiotic strains, including lactobacillus and bifidobacterium, are good for anxiety and depression, Dr Ho says. 

Lactobacillus rhamnosus, the probiotic bacteria most studied, is shown to reduce anxiety-like behaviours in animals. 

“It’s thought to work by the vagus nerve – an important nerve that connects the gut to the brain,” Dr Ho says. 

“Though, there’s a lot more evidence currently for animals than humans.”

How effective are psychobiotics on gut health?

A new Swiss study showed after four weeks of taking a probiotic supplement or placebo, the probiotic group of depressed patients had reduced depressive symptoms. 

“Participants in the probiotic group showed a change in the neuroimaging that correlated to improvements in depression,” Dr Ho says. 

“It’s really the first randomised trial of its kind. 

“The fact it correlates with brain imaging itself is really quite impressive. It’s very new.”

Don’t ditch your meds, yet

While there’s evidence different types of bacteria, or combinations of bacteria, can improve some symptoms of anxiety and depression, it’s still early days, Dr Ho says. 

“The fact it’s being studied now in humans is very exciting, but we’ve also got to temper that with realistic expectations. 

“If you’re on an antidepressant because you’ve been prescribed that by your psychiatrist, you shouldn’t just stop that and go on to a psychobiotic.

“Probiotics can be helpful, but it certainly shouldn’t at the moment replace medical therapies.”

Should we all take probiotics?

While premature to ditch conventional therapies, it’s still a good idea to consider improving your gut health, and potentially mental health, by including probiotics in your diet, Dr Ho says. 

It can be via natural probiotics, rather than pills. 

“Having that on a more regular basis itself can be very beneficial,” Dr Ho says.

Endeavour College nutrition educator and nutritionist Sophie Scott says the gut produces 95 per cent of our serotonin, the happy mood chemical, and studies showed those on a Mediterranean style diet are 33 per cent less likely to develop depression.

Which probiotic pill is best?

The jury’s out on which commercial probiotic is best, Dr Ho says. 

Pills vary by strains that have been studied for conditions such as anxiety, IBS and gastroenteritis, and there’s no “master pill”. 

People seeking probiotics for a specific condition should ask their pharmacist about the evidence behind it, he adds.

Are probiotic pills better than natural foods?

Pills are thought to be more beneficial than natural foods as they typically contain higher concentrations of bacteria, Dr Ho says. 

But consuming probiotic foods over a long period could be much more beneficial than taking a commercial probiotic pill for a short time, he adds.

To boost probiotics in your gut, Scott recommends eating fermented food daily such as kefir, yoghurt or kimchi, and including fibre-rich foods such as oats, bananas, rye bread, hummus, vegetables and nuts.

Written by Melissa Iaria.