A pilot study conducted by researchers at Johns Hopkins Medicine and Sheppard Pratt Health System, shows probiotics may provide psychiatric benefits in people, who do not have a history of yeast infections. By adding probiotics, beneficial microorganisms found in yogurts, goat’s milk and cheese, to the diet may reduce two common schizophrenia symptoms, hallucinations and delusions.
Fifty-six people, including 19 women, who had been diagnosed with schizophrenia, volunteered to participate in the study. The participants were 61 percent white, with an average age of 46. Participants were required to complete the Positive and Negative Syndrome Scale (PANSS) exam, a scale that is utilized for measuring the severity of schizophrenia symptoms, and submit a blood sample, before the trial commenced. PANSS scores are measured on a scale from zero to 24.
The researchers recommend further testing to validate the findings and to determine if women, who suffer with schizophrenia, respond in the same manner to probiotics, before this approach is recommended widely for treating schizophrenia.
“The mental health field is in desperate need of new treatments for psychiatric disorders, yet there’s been very little progress toward this goal for too long a time. The tiny living organisms that make up the human microbiome and the overwhelming evidence for a gut-brain axis together represent a new frontier for schizophrenia research,” says Emily Severance, Ph.D., assistant professor of pediatrics and part of the Stanley Division of Developmental Neurovirology at the Johns Hopkins University School of Medicine.
In the initial study, researchers examined links between probiotics and bowel function and probiotics and psychiatric symptoms in people, who were diagnosed with schizophrenia. The findings showed bowel improvement, with no changes in the psychiatric symptoms. A previous relevant study published this year, focused more on memory problems in people with schizophrenia and a history of candida yeast infections.
Each participant was administered a placebo daily with a meal for two weeks. At the end of the two weeks, the participants were split up into groups, so they or the researchers could not determine who would be administered the placebo or probiotic over a 14 week period. Every two weeks, the participants’ PANSS scores were reassessed and they rated their bowl movements on a scale of 0 to 4. At the conclusion of the study, participants submitted another blood sample, which was utilized to measure Candida albicans and Saccharomyces cerevisiae antibodies, commensal yeast species.
The findings showed probiotic treatment reduced Candida albicans antibodies by 43 percent in men over the 14-week study period. C. albicans antibodies levels were unchanged in women. S. cerevisiae antibodies levels were unchanged in both women and men.
For the next analysis, researchers focused on men with elevated Candida antibodies. Five men with Candida from the placebo group reported bowel problems, with an average 0.74 bowel score, compared to 10 men with no evidence of yeast infection, who had an average bowel score of 0.19. These findings were consistent with the 2014 analysis, but the study supports the idea that Candida yeast causes bowel problems in males with schizophrenia.
Next, researchers analyzed PANSS scores from a previous, larger schizophrenia study. PANSS scores measure schizophrenia symptoms on three separate levels, including positive, negative and general psychological.
- Positive symptoms – grandiosity, hallucinations and delusions
- Negative symptoms – poor socialization and social withdrawal
- General psychological symptoms – guilt, depression and anxiety
A total of 165 men, who tested positive for C. albicans antibodies, reported higher levels of positive symptoms, with an average PANSS score of 19.5, compared to 219 men, who had negative antibody test results, scored on average less than 18.5. Participants with a negative antibody test result that received probiotic treatment showed higher improvements, with the average PANSS score of 18 dropping to 14.6 after 13 weeks.
Researchers published the findings in the journal Brain, Behavior and Immunity.