Regulating Gut Bacteria

People who experience anxiety symptoms might be help taking steps to regulate the microorganisms; in their gut using probiotic and non-probiotic food and supplements; suggests a review of studies published today in the journal General Psychiatry. Anxiety symptoms are common in people with mental diseases and a variety of physical disorders, especially in disorders that are related to stress.

Previous studies have shown that as many as a third of people will be affected by anxiety symptoms; during their lifetime. Increasingly, research has indicated that gut-microbiota 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; can help regulate brain function through something called the “gut-brain axis.”

Recent research also suggests that mental disorders could be treat by regulating the intestinal microbiota; but there is no specific evidence to support this. Therefore a team of researchers from the Shanghai Mental Health Center at Shanghai Jiao Tong University School of Medicine; set out to investigate if there was evidence to support improvement of anxiety symptoms by regulating intestinal microbiota.

Non-probiotic ways

They reviewed 21 studies that had looked at 1,503 people collectively. Of the 21 studies, 14 had chosen probiotics as interventions to regulate intestinal microbiota (IRIFs); and seven chose non-probiotic ways, such as adjusting daily diets. 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.

The researchers found that 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.

Reduction in anxiety symptoms

Overall, 11 of the 21 studies showed a positive effect on anxiety symptoms by regulating intestinal microbiota; meaning that more than half (52%) of the studies showed this approach to be effective; although some studies that had used this approach did not find it worked.

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, while six of the remaining seven studies that had used non-probiotics; as interventions found those to be effective—a 86% rate of effectiveness.

Some studies had used both the IRIF (interventions to regulate intestinal microbiota) approach and treatment as usual. In the five studies that used treatment as usual and IRIF as interventions, only studies that had conducted non-probiotic ways got positive results, that showed a reduction in anxiety symptoms.