How your gut bacteria may be affecting your mood

What is the gut microbiota?

The gut microbiota is a complex and dynamic population of microorganisms, such as bacteria, that are found in the gastrointestinal (GI) tract. There are estimated to be over 1014 microorganisms in the gut microbiota which actually exceeds the number of human cells in the body. There is a symbiotic relationship between the body and the microbiota, meaning it is a mutually beneficial relationship. The microorganisms help to strengthen the gut integrity, harvest energy, protect against pathogens, and regulate immunity, while the host provides an environment for the bacteria to live.

What is the relationship between the gut and the mind?

The gut and the mind are connected by the gut-brain axis (GBA), which essentially is a communication system that links the emotional centers of the brain and the digestive tract. Because of this connection, the bacteria in your gut can have an affect on your mood, motivation, and higher cognitive functions.

Newer data is showing that the microbiota can have a role in anxiety and depressive-like behaviors. A direct link was found between the microbiota and the neurological pathway that releases stress hormones into the body (which can affect your stress levels by activating the vagus nerve in the GI tract).

Can taking probiotics help mood disorders?

Probiotics are foods or supplements that contain live microorganisms. Due to the findings of the relationship between the gut microbiota and mood, there is interest in whether probiotics can help mood disorders, especially for depression. There is some evidence that probiotics may help to alleviate depressive symptoms but further studies are needed to better understand dosage, duration of treatment, and type of probiotics that are needed.

Curious to learn more?

Naturopathic doctors are trained to support mood through a variety of modalities, including nutrition, supplementation, and pharmaceuticals.  If you want to learn more about how a naturopath can support you through depression or anxiety, you can call for a free meet and greet.

References

Thursby E, Juge N. Introduction to the human gut microbiota. Biochemical Journal. 2017 Jun 1;474(11):1823–36.

Carabotti M, Scirocco A, Maselli MA, Severi C. The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Ann Gastroenterol. 2015;28(2):203–9.

Wallace CJK, Milev R. The effects of probiotics on depressive symptoms in humans: a systematic review. Ann Gen Psychiatry. 2017 Dec;16(1):14.