Gluten’s Effects on Pregnancy (Part III): Mental Health

Gluten can affect many aspects of pregnancy. From fetal development to the risk of miscarriages and infertility.

This is the third post in a 3-part series. For additional readings on gluten’s effect on pregnancy please see my other articles:

Gluten’s Effects On Pregnancy (Part I): Celiac Disease
Gluten’s Effects On Pregnancy (Part II): Infertility

While there is still much to investigate, it does seem that the cascade of events resulting in schizophrenia begins while in Utero. (1.a) With that in mind, the benefits of maintaining a gluten-free diet while pregnant certainly outweigh the risks.

It is estimated that every Canadian will (at some point in life) be affected by a mental illness in a family member, friend, or colleague. (1) Mental illnesses are characterized by alterations in thinking, mood or behavior (or some combination thereof) associated with significant distress and impaired functioning over an extended period of time. (2)

For the purpose of this blog post, we will be examining gluten’s effects on schizophrenia.

What is schizophrenia?

Schizophrenia is a brain disease and one of the most serious mental illnesses in Canada. The prevalence of schizophrenia is between 0.2-2% of the population. (3)

The common symptoms of schizophrenia include (4):

• Delusions and/or hallucinations
• Lack of motivation
• Social withdrawal

You most likely associate schizophrenia with visual hallucinations. That is the typical depiction our society uses for schizophrenia. Though there can be other symptoms not commonly associated with the disease. These include: (5)

• Reduced expression of emotions through facial expressions or voice
• Reduced feelings of pleasure in everyday life
• Difficulty starting and/or sustaining activities
• Reduced speaking
• Decreased ability to understand information and use it to make decisions
• Trouble focusing or paying attention
• Challenges using information immediately after learning it

What causes schizophrenia? 

The cause of schizophrenia has not been narrowed down to a single, causative factor. Like most chronic illnesses, there are many moving parts. In my opinion, it is unlikely we will find a single causal element for schizophrenia. It’s likely a combination of factors. At the time of this writing, we know that there is a genetic component. Schizophrenia tends to run in families. However, there are many cases of schizophrenic individuals with no family history of the disease. (6)

Researchers believe that the interplay between a gene and its environment are required for the disease to develop. This branch of research is called epigenetics. The potential environmental stressors associated with schizophrenia include: (7)

• Exposure to viruses
• Malnutrition before birth
• Complications while in utero
• Psychosocial factors

A 2012 study found that intestinal inflammation was a common occurrence in schizophrenic patients. (8) This study thought that the inflammation was potentially caused by food allergies and/or a gut infection. Their hypothesis is that the immune reaction can contribute towards mental illness. (9)

Could gluten be a causative agent in schizophrenia? The research shows that there is a clear correlation.

Gluten and schizophrenia

Gluten’s contribution to the development of schizophrenia is not a new research finding. In fact, a study done in 1953 noted an increase in celiac disease among children suffering from schizophrenia. It was thought that gluten may be an environmental trigger for schizophrenia in genetically susceptible individuals. (10)

Observational research continued during the second world war. During this time, food supplies were scarce. Thus, gluten and wheat consumption decreased. It was found that admission to mental hospitals for schizophrenia decreased during this time frame. (11) However, in the USA (where wheat consumption increased) admissions to mental hospitals for schizophrenia increased. (12) A follow-up study found that inhabitants of South-Pacific islands had virtually no cases of schizophrenia. Their diets also contained almost no grains. (13)

Fast forward to modern times and you’ll find no shortage of research connecting gluten allergies/sensitivities to neurological conditions of unknown cause. One study found that 57% of patients with neurological dysfunction of unknown cause had evidence of a gluten sensitivity. (14)

A Danish study found a 3.2x increased risk of developing schizophrenia for individuals with a history of celiac disease. (15) But the true association between celiac disease/gluten sensitivity and schizophrenia may even be higher than these studies suggest. Celiac disease is often identified early in life. This results in the child removing gluten from his/her diet. Schizophrenia, on the other hand, most often manifests in adolescence or early adulthood. Adhering to a gluten-free diet in childhood may prevent the development of schizophrenia in certain cases. (16)

Yet another small study of 24 patients noted changes in their schizophrenic symptom profile in response to the removal of gluten from their diet. The entire group of 24 improved their symptoms by following a gluten-free diet. Even more surprising, two particular patients who had improved significantly during the gluten-free period worsened upon reintroduction of gluten into the diet. (17)

But before you go off thinking removing gluten is a panacea for mental illness, let us not neglect the studies that showed gluten removal had little effect. A small study found no differences in the functioning of 8 schizophrenic patients in an inpatient unit on measures of psychopathology following a gluten-free diet. (18) However, with celiac disease occurring in only 3% of the population it is quite plausible that in the sample size of only 8 patients, none of them had a gluten allergy.

Ultimately, we need more research. Specifically, research done on a large scale. The current research, while done on small populations, certainly points towards a connection between gluten and schizophrenia. But how could something as seemingly harmless as a protein such as gluten potentially trigger a serious mental illness?

How does gluten trigger schizophrenia?

While not accepted by the scientific community, there are countless reports and case studies of schizophrenic patients detailing complete remission of their symptoms following adherence to a gluten free diet. One documented case showed a woman with celiac disease and schizophrenia had complete symptom regression of both disorders after starting a gluten-free diet. Scans were taken before and after treatment and showed complete resolution of decreased blood flow to the frontal cortical aspect of her brain. This decreased blood flow is a common symptom associated with schizophrenia. (19)

Unfortunately, the exact mechanism connecting gluten and schizophrenia has yet to be uncovered. It’s not as simple as schizophrenia being a symptom of a food allergy. One current avenue of thought suggests that gluten may interfere with processes in the brain in certain genetically susceptible individuals by means of an autoimmune mechanism. (20)

Another theory explores how opioid peptides, called exorphins, can be absorbed into the bloodstream from the gut. Gluten exorphins are opioid peptides formed during the digestion of wheat proteins. Exorphins are able to pass through the blood–brain barrier and affect the brain (21). Schizophrenic patients show an increased amount of exorphins. These peptides can affect behavior and cause alterations in neurotransmitter levels (22)

Should you go gluten free?

Don’t take it from me, according to the World Health Organization (WHO) criteria, a policy of mass screening for the detection of celiac disease is justified. (23) Not only is it a common autoimmune disease, but it can be effectively treated simply by removing gluten. Given the reported association between schizophrenia and celiac disease, proper screening to rule in/out celiac disease is a great plan of action.

If you’re planning a pregnancy, I would strongly recommend taking a thorough family history. If there is any history of celiac disease or gluten sensitivity, ensure you’re gluten free throughout your pregnancy. Additionally, I’d recommend testing after pregnancy to determine the severity of your gluten allergy/sensitivity.

If there’s no history of celiac disease but there is a history of schizophrenia, again, I would strongly recommend implementing a gluten free diet. After pregnancy concludes, follow-up with additional testing to determine the severity of your gluten allergy/sensitivity.

Is it imperative to be gluten free while pregnant? 

This comes down to whether or not you’re at risk. At the time of this writing, it is known that your risk increases if you have:

• A family history of celiac disease
• A family history of schizophrenia

While there is still much to investigate, it does seem that the cascade of events resulting in schizophrenia begins while a baby is developing. With that in mind, the benefits of maintaining a gluten-free diet while pregnant certainly outweigh the risks.

Looking for more information? Check out our other blog posts about gluten.