Fueling Our “Second Brain”
December 3, 2023
Writer: Ella Javorsky
Editor: Leighton Gray
Just three years ago, I sat down for my daily social media scroll after school, and I found myself drawn to certain content on my TikTok’s “For You Page” that was foreign but intriguing. The clips were all about promoting good gut health and the importance of feeding our gut microbiome. As just a sophomore in high school, I thought to myself: “What is a gut microbiota?” The topic was new, but it resonated with me and my passion for nutrition and wellness. It was a start that transcended into a deep dive of microbiome-related research and a newfound appreciation for gut health. Three years later, as someone who battles IBS on a daily basis, I now understand what gut health is all about and recognize the instrumental role microbes play in all aspects of human health. I now see why our gut is said to be our “second brain.”
The gut-brain axis refers to the bidirectional relationship between the gastrointestinal tract and the brain through a system of nerves, neurons, and neurotransmitters. It is the communication system that links the emotional centers of the brain with peripheral intestinal functions. If you’re like younger me and were at a complete loss when first reading this definition, then think of it as the link between brain activity and processes performed by the gut microbiota, such as digestion. This connection is the reason why we often have upset stomachs while stressed and anxious about upcoming midterms, or the common feeling of “butterflies” in our stomachs before something exciting or nerve-wracking happens. The two organs are connected both physically and biochemically; as a result, the gut plays a leading role in processes like digestion and metabolism, as well as in our body’s stress response and cognitive functions like decision-making. The connection is complex, and it is currently being explored in relation to psychiatric illnesses, mental health conditions, and gastrointestinal diseases.
Given the power of these gut microbes, it is crucial that we are mindful of what we put into our bodies in order to nourish these species. If we deprive microbes of essential nutrients and vitamins, then they cannot perform at their maximum potential. There are small steps we can take to support a healthy brain and body connection. Here are some important food groups that are beneficial for the gut-brain axis.
Omega-3 and -6 fatty acids: These are essential fats that have been found to increase good bacteria in the gut and lower the risk of brain disorders. They are found in oily fish, like salmon, and in leafy vegetables, seeds, and nuts.
Fermented foods: Sometimes known as prebiotics, these foods all contain healthy microbes, including lactic acid bacteria, that help optimize microbe activity in the gut as well as produce neurotransmitters linked to mood. Yogurt, kefir, sauerkraut, pickles, and kombucha are just a few examples of these foods.
Whole foods and high-fiber foods: Whole grains, fruits, vegetables, fruits, and seeds all contain prebiotic fibers that fuel gut bacteria and regulate stress hormone levels in humans. These foods are also linked to a Mediterranean diet, which is said to be anti-inflammatory and gut-healthy.
Polyphenol-rich foods: Polyphenols are plant chemicals that are digested by gut bacteria and linked to improved cognition. Cocoa, green tea, olive oil, and coffee all contain this beneficial chemical.
Works Cited
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Image: Jules Bonanno
