The gut-brain connection has been present since the beginning of humankind, but the research on this connection has expanded significantly in the past decade.
Though the research is showing us more and more ways the gut and the brain communicate with each other, we still have unanswered questions: how does the microbiome affect a person’s mood? Can we modify the microbiome to support mental health? Where do probiotics come into play?
This is what we’ll focus on today: probiotics and the brain.
P R O B I O T I C S & M O O D – There are many proposed mechanisms as to how probiotics affect mood, but the pathway isn’t 100% clear. We have however seen some patterns on probiotics directly affecting mood in the research. Let’s take a look!
Many women can experience low moods after having a baby, so researchers wanted to see if probiotics could help. A 2017 study offered 423 pregnant women to take lactobacillus rhamnosus from 16 weeks gestation until 6 month after having the baby. Based on questionnaires completed by the women during postpartum, those who were taking the probiotic experience better coping and stress response as well as a healthier mood compared to controls.
Researchers also wondered if probiotics had any benefit on people experiencing sadness. A 2016 study gave 40 participants either a multispecies probiotic or placebo capsule for 8 weeks. After 4 weeks, the probiotic group were noted to have less cognitive reactivity to a sad mood.
P R O B I O T I C S & S T R E S S -- A study in 2016 evaluated whether probiotic consumption affected stress response and brain activity in healthy people under stress. Participants took probiotic Bifidobacterium longum for 4 weeks and completed a neurocognitive test and a stress test before and afterwards. Results show that consumption of this probiotic was associated with healthier stress responses and decreased stress-induced memory loss.
P R O B I O T I C S & C O G N I T I O N – So probiotics could potentially help with mood and with stress, but what about cognitive function? There is a test to measure cognitive function called the Mini Mental Status Exam (MMSE). A 2016 study gave the MMSE to 60 participants and were either given a probiotic drink or a placebo drink for 12 weeks. Results show that the probiotic supplement had positive effects on MMSE scores. *I have beef with this study because I don’t think it gave enough information on how the probiotic group did versus the placebo group, but it’s an interesting idea that is worth researching more.
Because this is an emerging field, there are only a small smattering of research articles published, but more are coming out every month. Our current knowledge on the subject is limited, but there’s a definite relationship seen. I’m excited to see what additional research comes out, and I’ll of course keep you posted! See my previous post on Gut Brain Connection for more research on this exciting topic!
Akkasheh G, Kashani-Poor Z, et al. Nutrition 32, no. 3 (2016): 256.
Papalini S, Michael F, et al. Neurobiol Stress 10 (2019): 100141.
Sanborn V, Azcarate-Peril MA, et al. Contemp Clin Trials Commun 12 (2018): 192-97
Slykerman RF, Hood F, et al. EBioMedicine 24 (2017): 159 – 65.