Probiotics can alleviate the effects of stress on cognition in healthy women

Dr. Mirjam Bloemendaal
About the Author

Mirjam Bloemendaal, is a neuropsychologist by training and obtained a Ph.D. in cognitive neuroimaging by studying cognitive aging using pharmacological and nutritional interventions. She is interested in the effect of physiological processes on mental health and behavioral performance.

What was the goal of your research or experiment?

Probiotics are living microorganisms intended to have health benefits when consumed in sufficient amounts. The use of probiotics can be advised for example when using antibiotics, aiming to protect and maintain a healthy and diverse community of gut bacteria, called the gut microbiota. Besides the role of the gut microbiota in intestinal health, awareness of their important role in mental health has increased. Hence, probiotics may – amongst others through their influence on the gut microbiota – prevent mood and stress-related symptoms.

In this study we therefore tested whether probiotics prevent negative effects of stress on cognitive performance through the gut microbiota.

How did you measure or test this?

Healthy, female participants used a multi-strain probiotics (Winclove Probiotics) for 28 days in a randomized controlled trial (probiotics group n=27, placebo group n=29). The participants also performed cognitive testing (working memory) after a stress inducing procedure, which included holding their hands in ice water for 3 minutes.

What were the main results or findings?

As expected, the stress procedure reduced cognitive performance, yet this negative effect was smaller in the participants who had received the probiotics. We also found that probiotics influenced the gut microbiota composition, and these changes were related to the effects on cognitive performance after stress. Participants with a higher increase in the relative abundance of the bacterial genus Ruminococcaceae_UCG-003, after using probiotics, were also the ones that were more protected from negative effects of stress on cognition. Ruminococcaceae_UCG-003 is a bacterium producing short-chain-fatty-acids, known for their beneficial effect on gut and brain health.

What does this mean?

This study shows that the gut microbiota are involved in the protecting effects of probiotics on cognitive performance in acute stress circumstances.

What is the next step?

Building on these results, this type of non-pharmacological interventions (i.e. probiotics) might aid in the treatment of mental health problems.

Publication information

Title: Probiotics-induced changes in gut microbial composition and its effects on cognitive performance after stress: exploratory analyses

Authors: Mirjam Bloemendaal & Joanna Szopinska-Tokov, Clara Belzer,  David Boverhoff, Silvia Papalini, Franziska Michels, Saskia van Hemert, Alejandro Arias Vasquez & Esther Aarts

Journal: Translational Psychiatry

Year: 2021