One of the reasons to avoid gluten is for its implicit link to mental disorders. There are several neurologic and psychiatric manifestations implicated with gluten sensitivity. One of them is psychosis. 

A study published in Nutrients examined the correlation between gluten and psychosis with non-celiac gluten sensitivity (NCGS) (1)

Researchers examined a case where gluten was a direct variable to the manifestation of psychosis. The study involved a 14-year-old girl who was admitted to a psychiatric ward. While the teen tested negative for celiac disease, she exhibited severe gastro-intestinal problems and other symptoms such as headaches, fatigue and weight loss. After several months a nutritionist put her on a gluten-free diet for symptomatic treatment of the intestinal complaints. A change emerged in her:

Unexpectedly, within a week of gluten-free diet, the symptoms (both gastro-intestinal and psychiatric) dramatically improved, and the GFD was continued for four months. Despite her efforts, she occasionally experienced inadvertent gluten exposures, which triggered the recurrence of her psychotic symptoms within about four hours.

The study presents a theory that psychosis may be a manifestation of NCGS. Nine months after starting a gluten-free diet, she remained free of psychotic episodes and gastro-intestinal problems. The girl’s mother reported that she became a “normal girl” again.

Non-celiac gluten sensitivity is a syndrome diagnosed in patients with symptoms that respond to removal of gluten from the diet after celiac disease and wheat allergy have been ruled out. 

It’s hypothesized that gluten peptides enter the blood through a “leaky gut”. That’s when gluten crosses the intestinal membrane and the blood brain barrier, affecting the system of neurons that produce opioids (a.k.a. the endogenous opiate system) and neurotransmission. Another possibility is that gluten peptides may set up an innate immune response in the brain similar to the gut mucosa, causing exposure from neuronal cells of a transglutaminase (an enzyme) primarily expressed in the brain. 

Another study published in Psychiatric Quarterly reviewed gluten as a possible causal mechanism for the onset of neurological and psychiatric manifestations in individuals with NCGS (2). Researchers summed up a hypothesis that neurologic and psychiatric complications seen in gluten sensitive patients may be the prime reason they are suffering from the diseases.

It’s easy for gluten sensitivity to go unrecognized and untreated in mental health patients. The study presented data suggesting that 22 percent of patients with celiac disease develop neurologic or psychiatric dysfunction and as many as 57 percent of people with neurological dysfunction of unknown origin test positive for anti-gliadin antibodies. Neurologic and psychiatric complications observed with gluten-mediated immune responses include a variety of disorders such as depression, bipolar disorder, schizophrenia, Autism Spectrum Disorders and others. 

While the role of celiac disease and neuro-psychiatric disorders are well understood, NCGS is not. Many studies show a correlation between anti-gluten antibodies and mental disorders. The correlation between mental illness and NCGS is less defined. More well-designed studies are needed to establish the real role of gluten as a triggering factor in neuro-psychiatric disorders.

More research is also needed to help disentangle celiac disease from NCGS and to understand the causes of gluten-associated neurologic and psychiatric complications. 

If you or a loved one is suffering from neurological symptoms or a mood disorder, consider a 6-12 week trial of a meticulously gluten free diet (best to take out animal dairy too while you are at it). To get the best answer of how impactful this could be, if there is an exposure, start the clock to zero and begin the trial again.