Gretchen Lidicker, M.S.

mbg Health Contributor

By Gretchen Lidicker, M.S.

mbg Health Contributor

Gretchen Lidicker earned her master’s degree in physiology with a focus on alternative medicine from Georgetown University. She is the author of “CBD Oil Everyday Secrets” and “Magnesium Everyday Secrets.”

A woman laying in bed covering her face.

Image by jamie grill atlas / Stocksy

June 11, 2023

Mental health issues are discussed more openly than ever before. Yet, when it comes to mental health conditions like depression, many people are still searching for a treatment that finally brings them relief.

But an exciting new study 1found that a very common compound may be able to move the needle on certain depression symptoms.


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Probiotics and depression

Symptoms of depression can be debilitating. They include apathy, guilt, hopelessness, changes in body weight, insomnia, and irritability. While these symptoms tend to be the primary focus of treatment, there’s also a long list of cognitive symptoms, such as difficulty concentrating, indecisiveness, and memory issues.

A new study shows that a popular supplement may help with the cognitive issues associated with depression. This randomized controlled trial including over 40 patients showed that high-dose probiotic supplementation for four weeks significantly enhanced memory and affected brain mechanisms underlying depression-based cognitive issues.

Results showed that people in the probiotic group have improved hippocampal function (the part of the brain in charge of emotion and memory) at the end of the study period.

As lead author Else Schneider, Ph.D., explained in an interview: “It supports our hypothesis that the hippocampus is the main structure that benefits from probiotics, and that’s why we only see improvement in the episodic memory and not in other cognitive domains, which are less hippocampus-dependent.”


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The gut-brain connection

While the study was small, the research, which was published in the Journal of Psychiatry and Neuroscience, adds to a growing body of evidence that there’s a strong connection between the gut microbiome, mental health, and cognition.  

For example, studies have shown2 that the gut microbiomes of people with depression are composed slightly differently than the gut microbiomes of those without the illness. We still don’t understand exactly how gut microbiome composition and depression are connected—for example, we aren’t sure whether an altered gut microbiome composition precedes or follows depression or how the two interact—but we know that the connection exists. Another study3 demonstrated that 30 days of probiotics led to a significant decrease in symptoms of anxiety and depression. 

This latest study can encourage all of us to support our gut health in honor of our mood, cognition, and mental health. Here are three habits to get you started: 


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The takeaway

A new study found that four weeks of probiotic supplementation may improve some of the cognitive symptoms of depression. While there’s still more we have to learn about the gut-brain connection, this research is yet another reminder to tend to your microbiome for the sake of your mood.