Multiple sclerosis (MS) is an autoimmune disease with an uncertain cause. However, recent research has linked it to gut microbes. We know that the Western diet, full of processed “foods” and remarkably high in sugar, is associated with many diseases, and we may soon be able to add MS to that list.
What is it about the Western diet that is so unhealthy? It appears to be the impact of those manufactured foods on the microbes that live in the gut, the microbiota. In particular, it seems that a species of helpful bacteria, Prevotella histicola, is being steadily exterminated by the Western diet. That is largely due to the diet’s lack of prebiotics, the fiber that feeds microbes in the colon.
Using a mouse model of MS, researchers found that by feeding the mice P. histicola, they could reduce the symptoms. Apparently P. histicola is able to chill out the immune system and prevent it from attacking the mouse’s own cells. If this work translates into humans, it will be a welcome development, as current treatments can have unpleasant side effects.
Because it affects the brain and because depression is common among MS sufferers, P. histicola acts here as a psychobiotic.
“In 2013, we defined a psychobiotic as a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness. As a class of probiotic, these bacteria are capable of producing and delivering neuroactive substances such as gamma-aminobutyric acid and serotonin, which act on the brain-gut axis. Preclinical evaluation in rodents suggests that certain psychobiotics possess antidepressant or anxiety-reducing activity. Effects may be mediated via the vagus nerve, spinal cord, or neuroendocrine systems.Recently we have suggested broadening the psychobiotic concept to include prebiotics—the fiber that acts as food for the psychobiotics.”
 Dinan, Timothy G., Catherine Stanton, and John F. Cryan. “Psychobiotics: A Novel Class of Psychotropic.” Biological Psychiatry 74, no. 10 (November 15, 2013): 720–26. doi:10.1016/j.biopsych.2013.05.001.
 Sarkar, Amar, Soili M. Lehto, Siobhán Harty, Timothy G. Dinan, John F. Cryan, and Philip W. J. Burnet. “Psychobiotics and the Manipulation of Bacteria–Gut–Brain Signals.” Trends in Neurosciences 39, no. 11 (November 1, 2016): 763–81. doi:10.1016/j.tins.2016.09.002.
The 2017 Gut Microbiome Conference (held at the Hyatt Regency Huntington Beach Resort and Spa — tough duty) was a celebration of the gut microbiota. Held from September 16-17, John Cryan gave a well-received lecture on psychobiotics. He discussed the brain’s Geppetto: microbes as puppeteers of neural function and behavior.
Written by science journalist Scott C. Anderson and the two leading researchers in the field, John F. Cryan and Ted Dinan, this information-rich guide to improving your mood explains how gut health drives psychological well-being, and how depression and anxiety can be relieved by adjusting your gut bacteria.
This groundbreaking book explains the revolutionary new science of psychobiotics and the discovery that your brain health and state of mind are intimately connected to your microbiota, that three-pound population of microbes living inside your intestines. Anderson tells the amazing story of the brilliant Irish researchers John F. Cryan and Ted Dinan, explaining how common mental health problems, particularly depression and anxiety, can be improved by caring for the gut microbiota. Science is proving that a healthy gut means a healthy mind—and this book details the steps you can take to change your mood and improve your life by nurturing your microbiota.