The Truth Behind “You Are What You Eat”

How an Unhealthy Gut Affects the Brain

Nutrition
October 4, 2021

Digestion issues can be excruciating. Stomach pain and intestinal woes are already unpleasant to deal with but did you know it can also impact your brain health?


There truly is a direct line of communication from your gut to your brain and vice versa. This connection is so profound that some even refer to it as the human body’s second brain. Your gut is sensitive to poor mental health and your brain will feel the effects of an unbalanced gut


This gut-brain connection is made possible by a component of the parasympathetic nervous system called the vagus nerve. You’ll often hear the connection called the gut-brain axis. This channel of communication makes it possible for the gut and the brain to exchange information. If either is in distress, it will send a signal through the vagus nerve to let its counterpart know. 


Some instances of anxiety and other mental distress can be traced back to the gut. Inflammation or an imbalance in the gut’s microbiome can lead to adverse mental health side effects. Anxiety, depression, and more can sometimes be a direct result of an unhealthy gut. So what is the real scoop on the gut-brain axis and how can you assure both of these parts of your body are in good shape?


Take a look into your gut health.

What Does an Unhealthy Microbiome Do to Your Brain? 

It is almost impossible to define a “normal” microbiome for the average human population. This complex population of microorganisms is established at birth and will change over time as new foods and environments are introduced. But regardless of what “normal” looks like from one gut to the next, it’s evident that inflammation caused by an unhealthy balance of microorganisms can lead to symptoms of depression and anxiety. Studies show this could be due to adrenal release of the stress hormone, cortisol. 

How to Improve Gut Bacteria Levels 

The phrase “you are what you eat” takes on a deeper meaning when we look at the gut. There’s growing evidence that what we put in our bodies has a direct impact on the microbiota thus impacting the vagus nerve and brain. The foods we eat and the supplements we take have a direct link to gut health. Luckily, there are ways to assure your gut bacteria levels are where they need to be. 

Processed Foods vs Whole Foods 

The bacteria in our gut feed off of what we eat. If you want to keep harmful microorganisms at bay, you should avoid the foods they thrive on. Instead, turn towards the type of nourishing foods the beneficial bacteria enjoy. Generally, a diet rich in fruits, veggies, and beans is ideal to maintain a healthy gut. This whole foods approach provides ample fiber necessary to safeguard good bacteria. 


Harmful bacteria can easily overtake beneficial bacteria if you provide them with the food they like. Processed foods can encourage the growth of unhealthy microorganisms in the gut. They swarm when provided a steady diet of added sugar, fat, and salt. Incorporating more high-fiber whole foods is one of the best ways to assure harmful bacteria don’t take over.     

Keep Up With Candida Albicans Levels 

There’s a diverse array of microorganisms, both good and bad, that can make their way into your gut. One especially problematic pathogen is Candida albicans. It’s a type of opportunistic, fast-spreading yeast that can cause issues such as thrush or urinary infections. This sneaky little microorganism can set up camp in your gut too. 


An overgrowth of C. albicans in the gut can get nasty fast. Studies show that high candida levels can cause Crohn’s disease and ulcers. Luckily, this microorganism has a similar diet to other harmful pathogens. Switching to a cleaner diet can help balance out the bacteria levels and squash a complete candida takeover. 

Probiotics and Prebiotics 

Gut health is a hot topic. In the last few years, more and more people have discovered the importance of keeping up a healthy microbiome. In response, the probiotic and prebiotic supplement market skyrocketed.


Pills, gummies, health drinks – you name it! There’s a wide selection of gut-supporting products at the public’s fingertips. But what exactly are probiotics and prebiotics and how do they help maintain a healthy microbiome?


Probiotics are a food or a supplement that contains live bacteria. Popular options include yogurt, kombucha, gummy supplements, and fermented foods such as kimchi. While a probiotic can be helpful, it’s important to be wary when selecting one. A good rule of thumb is to stick with a product that delivers at least 1 billion colony-forming units (CFU) per serving. You should also be sure it lists the specific bacteria it contains. Lactobacillus, Bifidobacterium, or Saccharomyces boulardii are all varieties that are proven to support the gut. 


Prebiotics are meant to support the healthy bacteria you already have in your gut. Essentially, they are a type of plant fiber that the human body cannot digest on its own. Beneficial microorganisms thrive off of prebiotics and will multiply when you incorporate them into your diet. While there are prebiotic supplements on the market, you can just as easily take in prebiotics by eating foods such as garlic, asparagus, bananas, and oats. 

Your Brain Can Affect Your Gut Too

Have you ever felt nauseous before an important job interview? This was the gut-brain connection at work. Not only can the gut affect your mental health, but your mental state can also influence your GI system. Medical professionals agree that certain digestive symptoms can be alleviated through psychology-based treatments such as cognitive-behavioral therapy (CBT) or antidepressants

How Your Immune System Comes Into Play 

An unhealthy gut has far-reaching consequences beyond just mental health. The microbiome can also affect the immune system. Harmful bacteria can lead to an array of issues such as irritable bowel syndrome (IBS), Crohn's disease, Ulcerative colitis, or even cancer. Furthermore, scientists have observed that certain illnesses can completely transform the microbiome. One study showed that tuberculosis ravaged the microbiome of a mouse replacing it with a completely new set of bacteria. 

Protect Your Gut 

We’re continuing to learn more about how the gut and the microorganisms that call it home affect the rest of the body. Right now it’s clear that there is an undeniable connection between the brain and the GI system. A healthy gut is linked to a stronger immune system, improved mood, healthy heart, and more. While there is still a lot we don’t know about the connection between a healthy gut and overall well-being, it’s clear that it pays to eat foods that support your microbiome. So if you’re having trouble with brain fog, depression, or anxiety, do your brain a favor and take care of your gut. 


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