What’s the most critical relationships in your life? It’s the relationship between your gut and brain, called the gut-brain connection. Every event in your gut and digestion can change your brain function, mood, and mental well-being. They’re not only created in mind; they are also created in the gut.

What’s gut-brain connection? 

The gut-brain connection means the relationship between the Enteric Nervous System (the nervous system in the digestive tract) and the Central Nervous System (brain, spinal cord, and retina of your eyes). These two nervous systems are connected via the vagus nerve, a long nerve connecting the brain to several other internal organs and relaying messages between them. The gut and brain “communicate” via this nerve directly and indirectly via molecules and hormones through blood circulation.

Vagus Nerve and the gut-brain communication 

Food molecules can stimulate the Vagus nerve in the digestive tract, and therefore every food and nutrient you eat has the potential to change your brain states. For example, eating a piece of chocolate stimulate neuropod cells in the gut, which connect to the vagus nerve. The signal travels to the brain, which, as a consequence, produces dopamine. It also leads to a sense of pleasure and reward. Similarly, eating something inflammatory will also affect the vagus nerve and initiate a stress state in the brain. It also leads to unhealthy behaviors and depressive symptoms. 

Gut microbiome and mental health

Also, gut microbes, the billions of micro-organisms like bacteria and fungi, affect this communication. They’re one of the most important links between the gut and brain signaling. They’re responsible for the gut immune defense, food breakdown, vitamin production, and neurotransmitter production in the gut.

Changes in the gut microbiome have been shown to alter the neural networks that control the stress response. Studies have also found altered microbiome in people who suffers from depression, anxiety, schizophrenia, and even Alzheimer’s Disease. And colonizing the gut with healthy bacteria can alleviate these symptoms. This shows how significant a role the gut microbiome has in mental health and even neural aging.

Good and bad gut microbes

The gut contains good and bad bacteria (health-promoting and pathogenic). Good bacteria help digest food and produce enzymes, neurotransmitters, vitamin K, and folic acids, and absorb vitamins. They also support the immune defense.  The most commonly known healthy gut bacteria species are Bacteroidetes, Firmicutes, Actinobacteria, Proteobacteria, Fusobacteria, and Verrycomicrobia.  Pathogenic bacteria (“bad bacteria”), cause inflammation and distress in the body; these include for example, Salmonella, E.Coli, and staphylococcus.

Things that disrupt the gut-brain connection are a lack of good bacteria, the incorrect ratio of good and bad bacteria, low diversity of good bacteria, or gut bacteria-diet mismatch. Therefore, a healthy diet that supports the gut microbiome is one of the most important ways to support mental health, stress recovery, positive mood, and mental energy. 

How to improve the gut-brain connection with diet? 

1. Eat Fermented foods

Healthy gut bacteria are formed through fermentation, and therefore fermented foods naturally contain healthy gut bacteria. Increasing the intake of fermented foods has been shown to improve the levels and variety of beneficial gut bacteria, reduce gut inflammation, and improve executive functions, cognitive scores, and mood. 

Fermented foods include, for example, yogurt, kimchi, kefir, sauerkraut, tempeh, natto, and miso. 

When you start eating fermented foods, start gradually. Consuming high amounts of fermented foods, if you’re not used to them, can cause digestive discomfort.

2. Eat plenty of fruits and vegetables and consume some coffee and tea

Polyphenols are plant compounds that are also potent antioxidants. They fight inflammation and protect the cells from damage. Polyphenols are also shown to reduce depressive symptoms and improve mood.

Polyphenols and gut microbiomes have a symbiotic relationship. Polyphenols stimulate the growth of health-promoting gut bacteria, like Lactobacillus and Bifidobacteria, and inhibit the growth of pathogenic gut bacteria.

Then again, the gut microbiome helps to transform polyphenols from the food to forms that can pass to the blood circulation and brain to improve health.

The American Gut Study showed that eating 30 different plants per week was better for the gut microbiome than eating less than 10. It may sound like a lot, but remember that spices and herbs also count. 

One of the most significant sources of different types of polyphenols is coffee. Drinking coffee is also associated with improvements in the gut microbiome, as well as tea and other polyphenol-rich drinks.

3. Consider using Probiotics

Probiotics mean for life. Probiotic supplements are available on the market without a prescription. They contain healthy living bacteria inside the supplement, commonly Lactobacillus and Bifidobacterium, but there can be other strains as well.

Probiotic supplements can be used when there’s a need to correct the microbiome. For instance, a clinician may recommend them after antibiotics, immunosuppressive medications, surgery, or for people with inflammatory gut diseases.

Even though probiotics can be bought freely, they’re not a one-size-fits-all solution. Their effectiveness depends on the person’s individual needs and the state of the gut microbiome. Additionally, an effective probiotic supplement must contain the correct amount of the right living, viable microbes, and they must be consumed for a specific time.

Unfortunately, many consumer products contain nonviable bacteria, or non-optimal amounts, too little or even too much, making them ineffective and, in worst cases, harmful. It’s also found that 39 % of consumer products contain different amounts of bacteria claimed in the bottle.

So when considering probiotics, you should consult your physician and preferably have your gut microbiome tested before starting any gut-altering supplement.

4. Eat high-fiber foods

Some studies suggest that dietary fiber also supports the gut microbiome by feeding the bacteria in the gut. Most dietary fibers are so-called prebiotics which means that the gut bacteria ferment them to Short-Chain Fatty Acids and use them as their nutrition. 

High-fiber diets and special kinds of plant fibers called prebiotics are linked to an increased abundance of Bifidobacterium and Lactobacillus but not increased gut microbiome diversity. This makes sense because they would instead feed the bacteria already in the gut rather than create new species.

According to studies, a fiber-rich diet support digestion in many other ways as well.

High-fiber diets are usually rich in polyphenol-rich vegetables, fruits, legumes, and whole grains and lower in processed meat. This diet composition can make fiber-rich diets less inflammatory than, for example, the typical western diet.

5. Eat natural foods instead of processed ones

Reducing inflammatory foods seems to be crucial for a healthy gut microbiome. Some foods that are typical for the western diet have been shown to reduce the diversity of the gut microbiome and increase pathogenic bacteria and inflammation. These include ultra-processed foods, simple sugars, oxidized fat, cooking-produced toxins, microplastics, and food additives like emulsifiers. Also, burned and spoiled foods are inflammatory.

Optin for natural and organic foods that are minimally processed and preferably seasonal can help manage gut inflammation. Natural foods from the supermarket’s fresh food section, vegetable aisle, and fruit aisle provide a lot of vitamins, polyphenols, and fiber that can support the gut microbiome.

There’s preliminary evidence that sweetener sucralose and saccharin may disrupt the gut microbiome for sensitive individuals, but possibly not for everyone in small amounts. There are not enough studies yet to make any reliable conclusion on these.

6. Reduce environmental toxins: choose organic and natural. 

Environmental toxins can travel through the gut through foods, skin, and drinking water. Exposure to environmental pollutants has also been shown to disrupt and elevate the risk of inflammation. These include arsenic, pesticides, antibiotics, heavy metals, and xenobiotics.

These habits help you to avoid the most common environmental toxins:

• Filter your tap water
• Get foods from farms
• Avoid rice cereals and low-quality rice
• Wash your food before cooking (also meat)
• Buy your fruit and veggies organic and local
• Peel and/or boil fruits and vegetables that are non-organic
• Swap household cleaning products for organic ones
• Swap household textiles for Oeko-Tex materials
• Swap cosmetics, toothpaste, shampoo, and soap for natural and organic ones
• Purchase a high-quality air purifier for home

Summary

This article discussed the relationship between the gut microbiome and how to improve it to improve brain health and mental health naturally.

Gut and brain communicate via food molecules, the gut microbiome, and the vagus nerve, and supporting gut health and gut microbiome may improve mental health and wellbeing.

You can support your gut microbiome by consuming fermented foods, plant polyphenols, and non-processed natural foods. You may also consider a probiotic supplement, but you should consult your physician first. Finally, avoiding highly-processed foods and environmental toxins also support gut health.

I hope you found this interesting, helpful, and practical. xo, Inka Land

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