Our gut microbiota is the trillions of microorganisms in the gut which perform important functions in the immune system and metabolism by providing essential inflammatory mediators, nutrients, and vitamins. It can help regulate brain function through something called the “gut-brain axis.”
Studies providing evidence that point to our gut bacteria playing a major role in our overall health are piling up. We have recently covered how the gut microbiome may have a hand in obesity, multiple sclerosis, and depression; as well as how artificial sweeteners have a toxic effect on gut bacteria. Next, we will cover new research which suggests that regulating intestinal microbiota may help relieve the symptoms of anxiety too.
They say there is no solid proof yet, however, it is clear from the growing body of scientific literature that our gut bacteria play complex roles in maintaining and impacting good health, whether that be to stay physically fit, happy, less anxious, or otherwise.
Compiling Research
A group of researchers recently decided to analyze studies that have been conducted to date on how regulating intestinal microbiota may help relieve the symptoms of anxiety and other mental disorders. What they found was that the bacteria that naturally populate the human gut may play an extensive role not just in a person’s physical health, but also in their mental well-being. Their findings suggested that our gut bacteria may influence certain brain mechanisms and contribute to anxiety.
The team, from the Shanghai Mental Health Center at Shanghai Jiao Tong University School of Medicine in China, evaluated the evidence of 21 studies. There were a total of 1,503 participants involved in all. Their focus was to look at all the different interventions set to regulate the intestinal microbiota and whether they had any effect on symptoms of anxiety. They published their findings in the Journal of General Psychiatry.
The Review:
- Probiotics are living organisms found naturally in some foods that are also known as “good” or “friendly” bacteria because they fight against harmful bacteria and prevent them from settling in the gut.
- 14 of the 21 studies had chosen probiotics as interventions to regulate intestinal microbiota (IRIFs).
Probiotic supplements in seven studies within their analysis contained only one kind of probiotic, two studies used a product that contained two kinds of probiotics, and the supplements used in the other five studies included at least three kinds. - 7 chose non-probiotic ways, such as adjusting daily diets.
- 11 of the 21 studies (52%) showed a positive effect on anxiety symptoms by regulating intestinal microbiota, meaning that this approach seems to be more effective than not.
- Of the 14 studies that had used probiotics as the intervention, more than a third (36%) found them to be effective in reducing anxiety symptoms.
- 6 of the remaining 7 studies (86%) that had used non-probiotics as interventions found those to be effective.
- 5 studies had used both the IRIFs (interventions to regulate intestinal microbiota) approach and traditional treatment. Of these, only studies that had conducted non-probiotic ways got positive results.
Non-probiotic Verses Probiotic
Non-probiotic interventions on their own seemed to have a greater positive effect than interventions using probiotics, at a rate of 80% effectiveness in the former versus 45% effectiveness in the latter.
This could be because of the fact that changing diet (a diverse energy source) could have more of an impact on gut bacteria growth than introducing specific types of bacteria in a probiotic supplement. “The energy source of gut microbiota growth is mainly food,” explain the study authors. “Adjusting the gut microbiota through modulating dietary structure can directly change the energy-supplying structure of gut microbiota and this plays a decisive role in the growth of gut microbiota, so the effect is obvious.”
A second reason could be because some studies had involved introducing different types of probiotics simultaneously. As a result, they could have fought against each other inhibiting either from working effectively.
A third reason could be because many of the intervention times used might have been too short to significantly increase the abundance of imported bacteria.
Conclusion
Many disorders are related to stress, and we do live in stressful times, which is why as many as a third of the population will be affected by anxiety symptoms during their lifetime. Anxiety symptoms are common in people with mental diseases as well as a variety of physical disorders. This research review reveals why scientists should not ignore the possible role of the intestinal flora when providing solutions for mental health. “Especially for patients with somatic diseases who are not suitable for the application of psychiatric drugs for anxiety treatment, probiotic methods and/or nonprobiotic ways […] can be applied flexibly according to clinical conditions,” the researchers conclude.
Another study we reported on last month found that foods high in fiber such as fruits, vegetables, and whole grains had a more positive effect on gut flora diversity. These dietary changes in combination with immunotherapy were more than five times as likely to shrink tumors than those taking probiotics and immunotherapy. Those taking probiotics actually had reduced gut flora diversity suggesting diet to be a better way to improve gut flora diversity than probiotic supplements. You can read the article by clicking here.
Overall, adjusting one’s daily diet might contribute more to regulating the microbiome by offering different sources of energy to the bacteria that populate the intestines. Furthermore, if people who experience anxiety symptoms, small or large, could be helped by just taking steps to regulate the microorganisms in their gut using probiotic and non-probiotic food and supplements, then that’s wonderfully simple!
