How Your Gut Microbiome Changes Your Thoughts

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A growing body of evidence suggests that what happens in our gut can influence our cognition, which means it alters the way we think. Specifically, the gut microbiome (the trillions of microbes living in our gastrointestinal tract) are thought to connect to and influence brain function through the gut-brain axis (the two-way connection between gut and brain). Here are just a few of the interesting ways in which the gut microbiome may impact our thoughts.

The gut microbiome generates a range of molecules that may impact brain function

The gut microbiome is tremendously active, both in breaking down molecules and creating new ones. In fact, the bacteria in our gut produce and metabolize a wide range of molecules that may either directly or indirectly affect our brain function. A good example is that our gut microbes can produce short-chain fatty acids (SCFAs), tiny fats that are linked (mostly in pre-clinical research) to improvements in cognition for certain populations. Gut microbes can also synthesize amino acids and vitamins that are key to a variety of brain processes. However, it’s still unclear to what extent the nutrients created by the gut microbiome are actually available to the brain.

The gut microbiome may alter cognition through the immune system

The gut microbiome also speaks to and may influence the brain by way of the immune system. Alterations in immunity (specifically, elevation in chronic inflammation) are linked to an increased risk for developing diminished cognitive function, including risk for Alzheimer’s dementia. Very high spikes in inflammation (as are sometimes seen in critically ill patients) are linked to delirium, a state of confusion, and generally altered mental status. Since the gut microbiome directly communicates with and influences immune cells (which are mostly located in the gut), the link between immunity, cognition, and the gut microbiome is certainly worth knowing.

How about the link between food, the gut microbiome, and cognition?

With trillions of individual bacteria that are being affected each day by our dietary choices, the gut microbiome is very responsive to our diet. Consuming the standard American diet (or “Western diet”) which is rich in processed foods, less-healthy fats, and added sugars is thought to contribute to a less-healthy microbiome. Having a less-healthy makeup of the gut microbiome. with more species of bacteria that produce inflammatory molecules (which seems to happen as we age as well as with an unhealthy lifestyle) has itself been linked to Alzheimer’s disease. These are a few of the reasons why so many health experts recommend a diet filled with a diversity of colorful fruits, vegetables, and other forms of fiber that are linked to better health of the gut microbiome.

What does it all mean?

To summarize this somewhat complex science, the gut microbiome may act on our brains and change our cognitive state through a variety of pathways, but the immune (which includes inflammation) and metabolic (including short-chain fatty acids) pathways may be two of the most important. This science furthers the idea that choosing a lifestyle that benefits the health of our gut microbiome may represent a long-term investment in our brain health. For information on how to foster an overall healthier gut-brain connection, including a healthier gut microbiome, this article offers a number of practical tips.