In our intestines live trillions of good bacteria that are important for body health. Not only does it help digest food, these good bacteria in the gut also play a role in building immunity and fighting disease-causing pathogenic bacteria.
But who would have thought, according to research, gut bacteria also play a role in preventing depression and anxiety disorders, you know. How could that be? Here’s an explanation.
1. The link between the digestive tract and the brain is called the Gut-Brain-Axis
According to a review of various studies published in the journal Annals of Gastroenterology, our digestive tract and brain are interconnected. This relationship occurs as a result of a reciprocal system between the central nervous system, the hypothalamic pituitary adrenal system (HPA) and the enteric nervous system in the intestine which is known as the Gut-Brain-Axis (GBA).
The HPA is the part of our brain that responds to stress. When we are hit by emotions and stress from the environment, the HPA in our brain is activated so that it stimulates the release of the hormone cortisol which is known as the stress hormone.
In addition, simultaneously, HPA also affects systems in the digestive tract such as the enteric nervous system as well as the lining of the muscles that affect bowel movements and the mucosa that protects the intestines.
2. Then how can gut bacteria affect the brain?
In the above review, it was explained that animals that were previously given a probiotic combination formula containing Lactobacillus helveticus R0053 and Bifdobacterium longum R1075 experienced improved intestinal surface integrity. In addition, HPA activity in these animals also decreased, as indicated by a decrease in the level of the hormone cortisol in the blood plasma.
Gut microbes also interact with GBA through communication with the sensory nervous system. In this study, gut microbes can affect the enteric nervous system by producing compounds that resemble neurotransmitter compounds such as GABA, serotonin, melatonin and acetylcholine. This occurs in animals that are induced with the probiotic Lactobacillus reuteri through their food.
Furthermore, evidence suggests that gut microbes’ ability to influence the brain involves a nerve called the vagus nerve. These nerves are responsible for transmitting information from our intestines to the central nervous system.
This was shown when mice with intestinal inflammation were removed from the vagus nerve, the sedative effect of probiotics with Bifdobacterium longum did not appear.
3. The benefits of good bacteria in dealing with stress
The benefits of probiotics for maintaining mood have been widely studied before. Research in humans shows that consumption of probiotic-containing drinks can reduce symptoms of depression and anxiety.
Published in the European journal of Clinical Nutrition, patients with chronic stress are given probiotic therapy containing Bifdobacterium species for three weeks. As a result, patients with poor stress conditions showed a good response to therapy, which was marked by improvements in mood and cognitive function.
In another study conducted by Messaoudi that was published in the British Journal of Nutrition, healthy volunteers without depressive symptoms were given probiotic supplements for 30 days. The volunteers were compared with another group who were given antidepressant drug therapy.
Apparently, the group that consumed probiotics had lower levels of cortisol in the blood. It was also reported that the psychological effects felt were equivalent to therapy with sedatives.
Well, already know right? It turns out that our brain and gut are closely related to affect our mood. There’s nothing wrong with starting to consume probiotic products that contain good bacteria to maintain our gut and mental health starting today.
