A HEALTHY INTESTINE GIVES US HAPPINESS

by Marta Marcè

Surely you have experienced the relationship between being nervous, anxious or stressed and its expression in our digestive system . Now the “ nerves in the stomach” have a scientific explanation and in recent years some fascinating data has been discovered about the role of the intestine and its inhabitants (the microbiota) on the nervous system, our emotions and stress management.

For example, we know that the enterochromaffin cells of the intestinal mucosa are responsible for synthesizing and storing up to 90% of the serotonin in our body. Serotonin is the neurotransmitter that on an emotional level gives us a feeling of happiness and its deficiency is related to depression. It is also the precursor of melatonin, so if its levels drop it can also cause insomnia. The neurotransmitter GABA , with inhibitory effects that allow us to relax , is also produced in the intestine and a direct relationship with a specific bacteria in our microbiota, L. rhamnosus, has been studied. Other neurotransmitters such as dopamine (pleasure) also depend on their intestinal synthesis and the good function of the microbiota.

The role of the intestinal microbiota in our emotions is not only established by the production of neurotransmitters, it has been discovered that the intestine contains a neuronal network as broad and complex as the one we have in the brain . It is called the enteric nervous system (ENS) and its main functions are responsible for intestinal motility, but its direct connection with the central nervous system shows that it also directly influences our emotional state. The brain-gut relationship is a round trip. That is, when I am not emotionally well or I am going through a moment of stress, I can feel it at the digestive level with pain, “cramping”, urgency to go to the bathroom or the opposite, constipation, among others. But this relationship also exists the other way around, when my microbiota is not balanced I can feel worse emotionally, more easily to feel stressed and more difficult to connect with well-being and balance. A healthy intestine gives us happiness :)

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