Gut-Brain Connection: How Fermented Foods Boost Mental wellness

The gut-brain connection refers to the bidirectional communication pathway between the gastrointestinal system (the gut) and the brain. It involves a complex network of neurons, hormones, and chemicals that transmit signals between the two. This connection is significant because it influences various aspects of our well-being, including mood, cognition, and overall mental health. Emerging research suggests that disruptions in the gut-brain axis may contribute to conditions such as depression, anxiety, and even neurodegenerative diseases. Understanding and nurturing this connection through dietary interventions, such as consuming fermented foods, can have positive effects on mental well-being.  

What Is Fermented Food?  

Fermented food refers to food items that have undergone a process called fermentation, where beneficial microorganisms like bacteria, yeast, or fungi convert sugars or carbohydrates into acids, alcohol, or gases. This process helps preserve the food, enhance its flavour, and increase its nutritional value. Fermented foods can include a wide range of options, such as sauerkraut, kimchi, yoghurt, kefir, kombucha, and pickles. These foods often contain probiotics, which are beneficial bacteria that can support gut health and have potentially positive effects on digestion and overall well-being. 

Understanding the Gut Microbiome  

The gut microbiome refers to the diverse community of microorganisms, including bacteria, viruses, and fungi, that inhabit the digestive tract. It is estimated that trillions of these microorganisms reside in our gut. These microbes play a vital role in various aspects of our health. Gut bacteria aid in digestion by breaking down complex carbohydrates, fibre, and other substances that our bodies cannot digest on their own. They produce enzymes that help metabolise food and produce essential vitamins and nutrients. Additionally, gut bacteria support nutrient absorption by enhancing the surface area of the intestinal lining. 

The gut microbiome also interacts with the immune system, influencing its development and functioning. Beneficial gut bacteria can help regulate immune responses and protect against harmful pathogens. They also contribute to the development of gut-associated lymphoid tissue (GALT), an important part of the immune system located in the gut.  

The gut microbiome can influence brain function and behaviour through various mechanisms, including the production of neurotransmitters, immune system modulation, and the gut-brain communication pathway. Promising research suggests that restoring gut microbiome balance through interventions like consuming fermented foods rich in probiotics may have beneficial effects on mental well-being.  

Probiotics and Mental Health  

Probiotics, which are live beneficial bacteria, have gained significant attention for their potential impact on mental well-being. Research findings suggest that probiotics may play a role in alleviating symptoms of depression, anxiety, and stress.  

Several studies have investigated the effects of probiotics on mental health. A review of clinical trials found that certain probiotic strains, such as Lactobacillus acidophilus and Bifidobacterium bifidum, showed promise in reducing symptoms of depression and anxiety. Another study found that a combination of Lactobacillus helveticus and Bifidobacterium longum reduced psychological distress and improved mood in participants. 

The potential mechanisms by which probiotics influence mental health are not fully understood but may involve the gut-brain axis. Probiotics can modulate the production of neurotransmitters such as serotonin and gamma-aminobutyric acid (GABA), which are involved in regulating mood and anxiety. Probiotics also have anti-inflammatory effects and can positively impact the gut microbiome, which may indirectly influence mental well-being.  

Specific strains of probiotics that have shown promising results in improving mental health include Lactobacillus rhamnosus, Bifidobacterium breve, and Lactobacillus plantarum. These strains have been associated with reduced stress responses, improved mood, and decreased symptoms of anxiety and depression in various studies. 

Recipe For Sauerkrat 


1 medium-sized cabbage head  

1 tablespoon of sea salt (non-iodized)  

Optional: additional spices or flavourings like caraway seeds, juniper berries, or garlic (to taste)  


Large mixing bowl  

Fermentation container (glass jar, ceramic crock, or food-grade plastic container)  

Cabbage stomper or clean hands for packing the cabbage  

Weights or a fermentation weight to keep the cabbage submerged  

Cheesecloth or fermentation lid to cover the container  

Rubber band or string to secure the cover  


Clean and sanitise all the equipment you'll be using to ensure a hygienic fermentation process.  

Remove the outer leaves of the cabbage and set them aside. Cut the cabbage into quarters and remove the core. Finely shred the cabbage using a knife or a mandolin slicer. 

Place the shredded cabbage in a large mixing bowl. Add the salt to the cabbage and massage it with clean hands for about 5–10 minutes. This process helps draw out the cabbage's natural juices and creates a brine. 

If using additional spices or flavourings, add them to the cabbage and mix well to distribute the flavours evenly. 

Transfer the cabbage and its brine into the fermentation container. Pack the cabbage tightly, pressing it down to remove any air pockets and ensure it is submerged in its own brine. Leave a couple of inches of headspace at the top. 

Take one or two of the reserved cabbage leaves and fold them to fit the surface of the cabbage mixture. This will act as a barrier to keep the shredded cabbage submerged in the brine.  

Place weights on top of the cabbage leaves to keep everything under the brine. This can be a smaller jar filled with water or a dedicated fermentation weight.  

Cover the container with a clean cheesecloth or a fermentation lid, securing it with a rubber band or string. This allows gases to escape while preventing contaminants from entering.  

Place the container in a cool, dark place, away from direct sunlight, and let it ferment. The ideal temperature range for sauerkraut fermentation is around 65–75 °F (18–24 °C). 

Fermentation time can vary, but typically sauerkraut takes around 1-4 weeks to develop its desired flavour. Taste it periodically to check for your preferred level of tanginess. Remember to burp the container occasionally to release any built-up pressure.  

Once the sauerkraut has reached your desired taste, remove the weights and the cabbage leaves. Transfer the sauerkraut into clean, airtight jars, and store it in the refrigerator to slow down the fermentation process. Enjoy your homemade sauerkraut as a delicious and probiotic-rich addition to salads, sandwiches, or as a side dish.  

Note: It's important to maintain good hygiene throughout the fermentation process to prevent the growth of harmful bacteria. If at any point the sauerkraut develops an off-putting smell, taste, or mould, it's best to discard it and start again with fresh ingredients.  

Happy fermenting, and enjoy your homemade sauerkraut!