Eje Microbioma Intestino Cerebro

Microbiome Gut Brain Axis

Do you know the Microbiome Gut Brain Axis?

Over the course of human evolution, trillions of bacteria have established themselves in our intestines, forming our “Gut Microbiome.” Current research is revealing the profound effect of these microorganisms on our health, including our mental, psychological and neurological well-being.

Before moving forward, it is essential that we describe certain concepts:

- Intestinal Microbiota is the set of microorganisms present in the human body.
- Intestinal microbiome is the set of microorganisms present in the human body and their genes.
- Eubiosis refers to the state of balance, diversity and functionality of the microbiota.
- Dysbiosis is the imbalance and loss of functionality of the microbiota.

In recent years, it has been revealed that the intestinal microbiome can affect brain function and vice versa, therefore helping us to adapt to our environment at all times. This bidirectional signal occurs through the vagus nerve, which connects the brainstem to the intestine.

The following are some of the most common signs on which the Gut-Brain Axis is based:

Depression and anxiety

Although research in this area is in its early stages, various studies have already revealed the presence of digestive disorders and intestinal dysbiosis in people suffering from anxiety and depression. Which shows us the intimate relationship between our intestinal function and mental health.

In this sense, it is already a fact that more than 90% of serotonin, our mood neurotransmitter, is produced in the intestine under the influence of the microbiome. Likewise, in our intestine certain live microorganisms such as Lactobacillus Rhamnosus and Lactobacillus Plantarun can produce gamma-aminobutyric acid (GABA), our neurotransmitter responsible for a state of calm, stress management and anxiety control.

The increase in intestinal permeability (alteration of the selective barrier), related to gluten consumption, the use of antibiotics and dysbiosis (loss of bacterial balance), also plays a fundamental role, and could allow the incorporation into the circulation of substances derived from the intestine such as lipopolysaccharides (LPS), which are capable of triggering chronic inflammation processes and increasing the activity of the amygdala (region of the brain involved in the perception of fear), triggering depressive and anxious behaviors

The term “psychobiotic” describes a living organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illnesses. Research on the effect of probiotics on depression and anxiety in humans is continuous and is very present today. For now, it is a powerful perspective, encouraging us to think laterally about the factors that lead to poor mental health and how it can be supported holistically with nutrition and lifestyle habits.

Behavior and learning difficulties

Optimizing intestinal health, treating dysbiosis, permeability and digestion, is a clinical priority for people with autism or neurodevelopmental disorders.

Intestinal dysbiosis is frequently observed in children with autism, which often involves the excessive growth of bacteria such as Clostridium, which are capable of producing p-cresol, a metabolite present in the urine of these children, which inhibits the enzyme dopamine beta-hydroxylase (DBH), which converts dopamine to norepinephrine. All of this could lead to increased dopamine levels, which may underlie some of the behavioral aspects of autism, along with other factors such as poor toxin elimination.

The consumption of probiotic supplements may offer a treatment alternative for people with behavioral and learning difficulties, as they help maintain a healthy intestinal microbiota and thus reduce the excessive growth of harmful microorganisms such as Clostridium.

Neurodegenerative disease

Our intestine influences the health of our neurons and neurotransmission. Increased intestinal permeability is considered a condition prior to the development of autoimmune inflammatory diseases, such as Multiple Sclerosis. Likewise, gut dysbiosis, including reduced bacterial diversity, has been linked to cognitive decline, Alzheimer's and Parkinson's disease. This is why intestinal health is of essential consideration for those who suffer from neurodegenerative disorders or want to prevent them.

Do you have any of these conditions? If so, improving and restoring your intestinal function with the use of probiotics, prebiotics and nutrients such as L-glutamine may be a good starting point. We also recommend that you be guided by a professional expert in intestinal health, and support your changes with appropriate diet and lifestyle.

Nutritionist Valeria Riquelme V.

Extract translated and adapted from BioCare UK



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