Biome-powered brain: a healthy gut could mean a healthy mind

Author: Mark Hutchens (Contributing Author)

29 October 2019 Education Latest Science

The idea that there is a mind-body connection has of recent years been a dominant theme in mental health and neurological science.

That we can influence our mental health with our thoughts is now broadly accepted. Our thoughts affect our brain’s chemical messengers, called neurotransmitters, which facilitate communication within the brain and the body1,2. These neurotransmitters regulate most of our bodily functions, such as dealing with stress1,2. For instance, when practising gratitude, a surge of rewarding neurotransmitters, like dopamine, are released and as a result we experience increased alertness and upbeat feelings.3

Accepting the role our thoughts have on our mental health has led to a surge in practices such as mindfulness, which builds skills to consciously direct our attention. This increases our psychological flexibility to opt-out of harmful thinking and the resultant mental health consequences and symptoms. Awareness of the impact of our thoughts allows us to direct our attention to prevent the causes of mental health problems instead of only managing the mental health symptoms of unwanted thoughts.

Enter the microbiome …

It has always been understood that the health of the body affects mental wellbeing, but recent developments in understanding the role of the gut microbiome in mental health have essentially created a whole new field of enquiry. It also opens up a whole new opportunity for potential relief for people suffering from mental health concerns or diminished mental performance. Several pieces of research in the last year lend weight to the importance of the microbiome in mental health.

gut microbiome test

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What is the research saying?

One study4 found clear support for the link between depression, quality of life and the microbiome showing that gut bacteria are associated with mental health. The study found the potential of the gut microbiome to produce a dopamine-related substance was strongly associated with quality of life. Dopamine is a dominant neurotransmitter involved in depression. Two groups of bacteria, Coprococcus and Dialister were also found to be depleted in people with depression and positively associated with quality of life scores. Coprococcus is involved in making an anti-inflammatory substance called butyrate, and other studies have suggested that inflammation may be linked to depression4.

Recent research has also established that information can travel from the gut to the brain5 and has made links between the gut and anxiety.

Rats fed the bacteria L. rhamnosus for six weeks exhibited fewer signs of stress and anxiety. Researchers found changes in the activity of genes affecting the neurotransmitter, GABA.
GABA is an inhibitory neurotransmitter that typically dampens neural activity, its receptors being the target of many pharmaceutical drugs for treating anxiety disorders.

Another recent study6 showed common gut bacteria Firmicutes, Proteobacteria, and Bacteroidetes in the brain. The study was not clear whether the bacteria travelled up the vagus nerve, crossed the blood brain barrier or something else, but there they were. This led to speculation that the brain might have its own microbiome or be linked to the gut microbiome, which is kind of interesting when you consider that the brain is fueled by the gut.

Nourish the gut?

Microbiome profiling is an integral component of understanding the makeup of the gut and because of the direct association to the brain it can also be important in addressing mental health and wellness. Once understood through profiling, gut health can potentially be addressed and any possible negative consequences on mental health ameliorated.

Taking a stool sample to understand important functions of the gut microbiome.

Interested to see your personal gut microbiome profile? Learn more with Microba Insight™.

*While Microba attempts to make the information on this site as accurate as possible, the diet recommendations and views expressed here belong to the author and do not necessarily reflect those of Microba.

This microbiome test is not intended to be used to diagnose or treat medical conditions. A full disclaimer is available here


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