– the effect of probiotics on mental health –

It is well known that food that contains probiotics – like yoghurt, kefir, sauerkraut – is good for our health by playing a role in digestion and supporting the immune system. But did you know that they’re also improving your mental health?

Trillions of bacteria are living in our body, both “good” and “bad”. They call the “good” bacteria and microorganisms that are living in our gut the ‘gut microbiota’. Researchers found that there is a connection between the gut microbiota and mental health. Probiotics are playing a very important role in this, since they are helping to keep your gut healthy by containing “good”, “helpful” bacteria and live microorganisms.

We all have stressful periods in our life. An exam period, an important deadline at work or even travelling can cause distress. Stress can have a lot of negative effects on our health, it causes harm to our gut microbiota, which is connected to our immune system, and as I mentioned, now we know that it is also has a connection with our psychological health. That is why researchers started to explore the effects of probiotics intervention on mental health like anxiety, negative mood regulation, and worry.

Probiotics can change the cognitive and emotional processes through the gut-brain axis, which is related to anxiety – yes, for example yogurt can do that, isn’t that amazing?! So, this means that probiotics have the potential to help reduce your levels of anxiety.

Clinical studies showed that probiotics can decrease feelings of stress, and help reduce symptoms of depression and anxiety, cognitive reactivity and rumination. A research by Tran et al. (2019) found that probiotics can help decrease panic and neurophysiological anxiety, worry, negative affect and negative mood regulation. The participants of the research had to take probiotics with CFU (colony-forming unit) (which were commercially available) for 28 days daily and then they completed an exit survey. According to the results a ceiling effect was also detected, which suggests that participants with high distress reported higher levels of improvement than those with normative distress. This means that taking probiotics can have more anxiety-reducing effects when you are having higher level of distress.

It is also good to know that researchers also observed significant increases in positive affect, anxiety control, and mood regulation in the high level of stress group. Unfortunately, on the other hand, they found no significant improvement in the normative distress group.

To sum it up, taking probiotics with CFU (colony-forming unit) – as pills, or eating food that contains probiotics like yogurt, kimchi, etc. – can improve your mental health in stressful periods of your life. Hopefully, probiotics might be a good preventive mean and therapeutic tool to combat anxiety and factors connected to anxiety (e.g., worry, negative affect, mood regulation, & anxiety control) in the future.

– It is important to note that probiotics can cause side effects too, like digestive symptoms, skin problems and allergic reactions – if you experience side effects, stop using probiotics or contact your doctor. –



Nhan Tran , Masha Zhebrak, Christine Yacoub, Joseph Pelletier, Darby Hawley, The Gut-Brain Relationship: Investigating the effect of multispecies probiotics on anxiety in a randomized placebo-controlled trial of healthy young adults., Journal of Affective Disorders

(2019), doi: https://doi.org/10.1016/j.jad.2019.04.043

Blog post written by Fanni Vivien Adorjan, on 07/07/2019

Fanni Adorjan studies Clinical and Health Psychology in Budapest, Hungary and she is an intern at Willingness Hub.