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The ‘Gut-Brain Axis’ Explained

The gut-brain axis is a communication system between your gut and your brain.

The microbiota in your gut speaks to the neurons in your brain by way of the vagus nerve, one of the largest nerves connecting the gut and brain. The chemical signals are transmitted within milliseconds. The 500 million neurons in your gut are in direct contact with the billion neurons in your brain. That’s why they’re known as the ‘brain in your gut’.

Your microbiota refers to the microbes in your gut (not to be confused with the microbiome, which refers to the microorganisms and their genes in your gut). The microbiota can affect your behaviour.

Depression, autism, obesity and eating disorders have all been linked to an impaired gut, which means having a well-functioning gut-brain axis is extremely important. One study found that people with IBS and Crohn’s had reduced vagal tone, another correlation that gut issues are correlated to the gut-brain axis.


The two are also connected through neurotransmitters. These chemicals are produced in the brain and control feelings and emotions. One of the most important neurotransmitters is serotonin, also known as the ‘happy hormone’. A shocking 95% of serotonin is produced in the gut, not the other way around as most people would believe.

Another neurotransmitter produced by your gut microbes is gamma-aminobutyric acid (GABA), which controls feelings of fear and anxiety. Studies show that increased GABA can lower anxiety and depression-related behaviours.

Short-Chain Fatty Acids

The gut also produces short-chain fatty acids. SCFAs are the most abundant by-products of gut microbial activity and an important biomarker of gut health. The most abundant SCFAs are acetate, butyrate and propionate, all of which play vital roles supporting our mental health and physical health.

Acetate regulates gut pH, protects against pathogens and boosts the immune system.

Propionate has wide-reaching effects including anti-inflammation properties and controlling appetite and weight control. It has been found that consuming propionate can reduce food intake and reduce the reward the brain gets from consuming fattening foods.

Butyrate has several functions in the body. It helps prevent leaky gut, fights inflammation that causes irritable bowel syndrome, ulcerative colitis and Crohn’s disease, prevents diarrhea, improves blood circulation in the colon, helps protect against cancer and is essential for mental health.

To check your SCFA levels, try the Aguulp Gut Test, a world-first of its kind that measures SCFAs to pinpoint gut health. The results come in a comprehensive report that lets you know the exact SCFA breakdown in your gut and advises on diet and lifestyle changes specific to you.

Additionally, almost 70 per cent of your immune system cells are in your gut. That makes your gut a massive part of your immune health. Gut microbes control what gets into the body and what is excreted, hence affecting how well your immune system works. But if your gut is inflamed, as is common across the world thanks to our modern lifestyles, your immune system will have a harder time turning off. This can lead to leaky gut syndrome, which allows bad bacteria to cross the gut barrier and leak into the blood. Certain types of bacteria in the blood are associated with depression and mental illness.

Our Aguulp for Immunity solution is designed to keep your immune system functioning at its best. It is chockful of vitamin D, which has been shown to contribute to the normal functioning of the immune system.

How to Look After Your Gut-Brain Health

So how do you keep the gut-brain axis healthy? By making sure our guts are full of diverse bacteria and our brains are well fed with essential nutrients.

That’s why the first Aguulp solutions we came up with makes sure the gut-brain axis is healthy. The vitamins and minerals in Aguulp for Gut and Aguulp for Brain work symbiotically. Together, they can fight inflammation, IBS and Crohn’s, improve anxiety and depression, and increase focus and motivation. Try our Dual Pack now for a month to feel the difference for yourself.

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