Depressive disorders and changes in the gut microbiota are newly well documented, but which bacteria play a role? To keep it simple, I’ve made you a table to see which bacteria are increased in a patient suffering from depression, and which bacteria are in abundance in the non-depressed population:

Bacteria that have increased abundance in patients suffering from major depressive disorder Bacteria that have increased abundance in the non-depressive, healthy population



Clostridium XIX

Lachnospiracea incertae sedis


















Reference: Winek, K., Dirnagl, U. & Meisel, A. Neurotherapeutics (2016) 13: 762. doi:10.1007/s13311-016-0475-x

This list is not exhaustive, and may not be a reliable indicator for cause and effect when it comes to depression. New research appears all the time, such as this study that found the probiotic lactobacillus rhamnosus reduced depression and anxiety in healthy mice.

So what should we do about it?

  • Looking into using probiotics containing more of the strains shown in the second column would be a good place to start. There are not enough studies that research the role of individual bacteria as a treatment for depression, so if you suffer from a major depressive disorder you should talk to your doctor before trying any new course of self-treatment. The one I’ve found to have the best mix of strains that include the most helpful proven bacteria, including lactobacillus rhamnosus is the NatureWise time release available here from Amazon UK and here from Amazon US.
  • Understand this research is in its early days, and new information arrives all the time, so keep an eye out for research that mentions individual bacteria types, like lactobacillus rhamnosus that was mentioned above.
  • Read all about how to keep the right bacteria alive
  • Maintain a healthy population of gut bacteria through diet, stress management and probiotics.

using probiotics