Why Gut Health affects your mental health, immune system, fat loss and more.

Why Gut Health affects your mental health, immune system, fat loss and more.

The gut, or the gastrointestinal system, also referred to as the gastrointestinal tract, digestive system, or digestive tract, is a group of organs that includes the mouth, oesophagus, stomach, pancreas, liver, gallbladder, small intestine, colon, and rectum.

The gut microbiome is the entirety of microorganisms, bacteria, viruses, protozoa, and fungi, and their genetic material existing in the gastrointestinal tract. The gut microbiota involves all the bacteria residing in the gut.

In the past decade, the gut microbiota has been researched for its effect on many functions in the human body including metabolism, nutrition assimilation, immune, and neuroendocrine responses affecting our mental health.

What is "leaky gut"?

Small gaps in the intestinal wall called 'tight junctions' allow water and nutrients to pass through while blocking the passage of harmful substances. Loose tight junctions make the gut more permeable, allowing bacteria and toxins to pass from the gut into the bloodstream, which can cause widespread inflammation and possibly trigger a reaction from the immune system. This ‘condition’ is commonly referred to as “leaky gut”.

Adopting certain nutrition and lifestyle changes with regular collagen supplementation will help to heal your gut by providing the ‘building blocks’ essential to epithelial cell integrity.

Why do we need a healthy gut?

Mental health

Most of the ‘feel-good’ hormones are produced in our gut and then get transported to the brain via the Vagus nerve. That’s why the gut is often being called the second brain.

Serotonin is a natural antidepressant responsible for the regulation of mood, appetite, sleep, memory, and learning. 90-95% of our serotonin is produced in the gut.

Dopamine, the neurotransmitter for desire and motivation, helps us strive, focus and find things interesting. 50% of our dopamine is produced in the gut.

GABA, the calming neurotransmitter, is also produced in the gut. It improves sleep and focus, reduces anxiety, stress, and inflammation.

Immune system

70-80% of our immune cells are produced in our gut. An unhealthy inflamed gut weakens the immune system and makes the body prone to catching viruses and developing illnesses including an array of autoimmune disorders.

General health 

Inflamed gut, with increased permeability and low microbiota diversity, will make you feel ‘blah’ - not only mentally but also physically due to impaired nutrient absorption and assimilation.

In this scenario, even if you eat lots of vitamins either in the form of whole foods or by taking supplements, they will not get absorbed efficiently which will impact every physiological function in your body and eventually lead to developing nutrient deficiency-related issues and illnesses.  

Fat loss

The better your gut health the more you can eat and stay lean.

This is because the microbiome affects how many calories we use from the food we eat. If you have more "firmicutes", you will absorb more energy than if you have more "bacteroidetes".

Firmicutes thrive on sugars and if you eat lots of sugary and processed foods, these bugs will overgrow in your gut and make it hard for you to lose fat. Even without the firmicutes, if your gut is inflamed, the rest of your body is likely to suffer a low-grade inflammation as a result, which will significantly hinder your ability to burn fat.


The gut microbiome is important in regulating gene expression. Although we are born with a specific genetic make-up, which we can’t change, we can change the expression of our genes by up-regulating the good/beneficial ones and down-regulating the bad ones.

For example, if you have the so-called "obesity gene" (FTO) you can keep it down-regulated by keeping your gut healthy and never actually become obese.

What are the main culprits in poor gut health, microbiome imbalances, and inflammation?

  • Eating processed foods. Most processed foods contain sugar or sweeteners, artificial preservatives, harmful vegetable oils, and other additives that affect the microbiome and damage gut lining. Processed foods are generally low in fibre, which is food for the good gut bugs. 
  • Eating too much sugar or artificial sweeteners. Sugar destroys collagen, which is the main structural component in the gut lining.
  • Accidental chemical consumption such as drinking tap water or eating unwashed fruits and vegetables. Chlorine is added to water to destroy harmful bacteria. Drinking tap water every day will eventually affect all the bacteria in your gut; both good and bad. Fruits and vegetables are sprayed with harmful pesticides that destroy everything! Imagine what that does to your sensitive gut bugs.
  • Drinking alcohol every day (even one glass) destroys the collagen in your gut lining and contributes to inflammation.
  • Medication; especially antibiotics and painkillers are highly inflammatory and damaging.
  • Poor dental hygiene, which allows bacteria to grow out of balance in your mouth, affects the food breakdown, absorption, and your gut health down the line.
  • High levels of stress and anxiety, which causes inflammation due to chronically elevated cortisol. This will mainly weaken your immune system and ability to absorb nutrients. It will also worsen the anxiety and stress due to insufficient ‘good feel’ hormones and neurotransmitters.


Veronika Larisova

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