The link between gut bacteria, emotion outlook and behavior, research reveals
(NaturalHealth365) It turns out that gut bacteria may not only be crucial to gut health and immune system health; it could also play a role in mood disorders and overall emotional health and outlook. Studies out of Northeastern University in Boston and UCLA have now confirmed this link.
There is a particular strain of gut bacteria that depends on a key brain chemical for survival. The molecule is called GABA, and it is instrumental in calming the brain. A shortage of it could adversely affect emotional outlook and lead to mood disorders.
Harmful gut bacteria can lower GABA levels and lead to mood disorders
In their research, Philip Strandwitz and colleagues from Northeastern University of Boston found that the gut bacteria KLE1738 can only grow in the presence of GABA molecules. The research results were presented at the American Society for Microbiology in Boston. Abnormally low levels of GABA are linked with mood disorders and depression.
A 2011 experiment showed another gut bacteria strain, Lactobacillus rhamnosus, alters GABA activity and stress reactions in mice brains. When the vagus nerve was removed – the pathway between the brain and the gut – the link between the two was disconnected. The researchers are now looking to see if other gut bacteria types have a link to GABA and other brain molecules related to mood.
Gut bacteria linked with brain size and functioning
Another study out of UCLA has identified gut bacteria connected with brain areas that are associated with mood and emotionally driven behavior. The research was funded by Danone Research, the National Institutes of Health and the Ahmanson-Lovelace Brain Mapping Center.
The results highlight growing evidence that brain, gut and microbiota interactions have an important role in health, emotions and behavior. In the study, 40 women were tested both chemically and in terms of their brain waves during emotional responses while viewing images. They were divided into groups, with one group showing a higher gut composition of the Bacteroides bacterium, and the other having more Prevotella bacteria.
The Bacteroides group was found to have more robust insula and frontal cortex brain regions; these are areas that assist with complex information processing. Their hippocampus brain volumes were also larger; this area assists in memory processing.
Gut health is critical to physical, cognitive and emotional health
The Prevotella group had more synaptic connections in their attentional, emotional and sensory brain regions, but lower hippocampus volumes. They also had higher levels of anxiety, stress and irritability when viewing negative images than the Bacteroides group.
The results show there is a definite interaction between the brain and the gut microbiota. While it is not certain if both areas influence each other, there is clearly a relationship. Regardless, this information about gut bacteria and gut health is groundbreaking in terms of insights into the mind-body connection.
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