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The Gut Microbiome in First-Episode Psychosis

The Gut Microbiome in First-Episode Psychosis

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1. Hooper LV, Wong MH, Thelin A, et al. Molecular analysis of commensal host-microbial relationships in the intestine. Science. 2001;291:881-884.

2. Dinan TG, Borre YE, Cryan JF. Genomics of schizophrenia: time to consider the gut microbiome? Mol Psychiatry. 2014;19:1252-1257.

3. Schwarz E, Maukonen J, Hyytiainen T, et al. Analysis of microbiota in first episode psychosis identifies preliminary associations with symptom severity and treatment response. Schizophr Res. 2017 Apr 22. pii: S0920-9964(17)30204-9. doi: 10.1016/j.schres.2017.04.017. [Epub ahead of print]


I guess a major factor we don't know however is cause and effect. As stated the gut-brain relationship is bidirectional. It is generally accepted that psychological distress can cause gastrointestinal problems and likely changes to the gut microbiome. An illness as distressing as psychosis (which is both triggered by and significantly adds to psychological stress) is likely to have a significant impact on the gut microbiome. I wonder what the results would look like if controls were those suffering from other forms of mental illness or distress?

Adele @

While I am no doctor, I pose why can't it be that the changes in the gut CAUSE the psychosis and other mental illnesses? If the relationship is bidirectional could that be a cause? Our poor eating habits and processed foods are causing serious illnesses all over our bodies. Currently we treat the symptoms maybe we could be looking more into the CAUSE. Science should seriously consider the brain-gut connection, inflammation, nutrient deficiencies (some caused by medications), acid levels and hormones as potential causes of mental illness. This study gives me hope that science is looking for more answers other than patients are simply mentally ill.

Gail @

I agree with Gail!! MORE RESEARCH must examine the gut to brain correlation!!!

Bea @

Although I can understand where you both are coming from, there have been other studies showing a correlation between the mind and the gut, although not necessarily specific to psychosis, I have read other materials about a correlation between anxiety, depression, stress, and the gut. I do agree with you, however, that much more research need be done before this field is used to apply treatment methods to patients.

Kimberly @

This study reminds me of Dr. Henry Cotton at Trenton State at the turn of the 20th century. His theory was that psychosis was caused by focal infections. His treatment consisted of surgically removing portions of the gastrointestinal tract, teeth or whatever was thought to be causing the condition. His theories and treatments were respected within the psychiatric community, with Trenton State gaining a reputation as being at the forefront in the treatment of mental illness.

While Dr. Cotton claimed high cure rates, his data was found to be inaccurate. In fact, many patients developed infections from the surgery, leading to premature deaths.

The authors of the study are to be commended for their creative thinking.

Lawrence @

Any down side to altering he gut microbiome with probiotics and prebiotics in such patients, while awaiting larger RCT studies?
William O'Neill, MD

William @

The following comment is on behalf of the author:

Dr. O’Neill raises an interesting and important question. While presently the evidence does not support widespread use of probiotics in patients with psychosis, these agents are considered to be relatively safe.

Outside of psychosis, studies using probiotics have reported abdominal cramping, nausea, fever, soft stools, flatulence, and taste disturbances as adverse effects. Of note, the FDA has issued a warning that advises practitioners of the potential risks of using dietary supplements containing live bacteria or yeast in immunocompromised patients.

Readers are also referred to two previous RCTs of adjunctive probiotics in schizophrenia:

Probiotic normalization of Candida albicans in schizophrenia: A randomized, placebo-controlled, longitudinal pilot study.
Severance EG, Gressitt KL, Stallings CR, Katsafanas E, Schweinfurth LA, Savage CLG, Adamos MB, Sweeney KM, Origoni AE, Khushalani S, Dickerson FB, Yolken RH.
Brain Behav Immun. 2017 May;62:41-45.

Effect of probiotic supplementation on schizophrenia symptoms and association with gastrointestinal functioning: a randomized, placebo-controlled trial.
Dickerson FB, Stallings C, Origoni A, Katsafanas E, Savage CL, Schweinfurth LA, Goga J, Khushalani S, Yolken RH.
Prim Care Companion CNS Disord. 2014;16(1). pii: PCC.13m01579.

Brian Miller, MD, PhD, MPH
Associate Professor
Augusta University
Department of Psychiatry and Health Behavior
Augusta, Georgia
Schizophrenia Section Editor for Psychiatric Times

PsychTimes @

Those pre and probiotics aline cannot correct the gut esp. if the gut is really bad. Thus, a nutritional diet based on leafy greens and protein are best suited for defeating candida overgrowth! The diet would last months to two years depending on severity.

Bea @

Hi...can You tell me , please, can essetial oils (oregano oil) help defeating Candida overgrowth?
Thank You

branka @

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