Celiac Disease and Mental Health

In all my years of practicing medicine, it’s become increasingly clear that you can’t treat the mind without treating the body. Physical health and mental health consistently overlap and are intimately intertwined. Celiac disease, a condition that is frequently undiagnosed, is an example of this interplay that is often overlooked but can still be a critical factor for restoring mental health.

Celiac disease is usually thought of as a gastrointestinal condition causing diarrhea, malabsorption and weight loss. However, celiac disease is a systemic condition, causing numerous conditions throughout the body—even affecting the brain. As such, celiac disease should not be overlooked as a potential factor contributing to mental health conditions. For example, some of the latest research suggests a higher incidence of depression, anxiety, bipolar, eating disorders and attention-deficit/hyperactivity disorder in children diagnosed with celiac disease (Lebwohl 2021).

What is Celiac Disease?

Celiac disease is a condition caused by an intolerance to gluten, a protein found in wheat, barley, rye, triticale, spelt and other related grains. When gluten is consumed, the immune system initiates an inflammatory response that damages the intestinal tract. Once damaged, intestinal absorption can be compromised, leading to diarrhea, poor nutrition and weight loss.

While diagnosis rates have been increasing, due to both increased testing and increased incidence, a large percentage of individuals with celiac disease remain undiagnosed. Estimates suggest that around 1% of the population has celiac disease with approximately 80% of patients unaware of their condition (Rubio-Tapia 2012). Contributing to the problem is that some patients with celiac disease have minimal symptoms, while others may be misdiagnosed with irritable bowel syndrome (Ford 2009).

In diagnosed patients, treatment for celiac disease is the life-long elimination of gluten-containing foods.

How Does Celiac Disease Affect the Brain?

Effects of celiac disease on the brain and nervous system are not well understood. However, nutritional deficiencies, direct gluten toxicity and autoimmune antibodies are thought to play a role.

Deficiencies of B vitamins, including vitamin B12 have been documented. This, in turn, can lead to elevated homocysteine, a toxic amino acid known to cause neurological damage. In addition, deficiencies in vitamin D and vitamin E have also been found. Vitamin D has well known roles in brain health and neurological function (Mpandzou 2016).

Peptides derived from gluten, some of which have opiate activity, also have direct neurotoxic effects on brain cells in celiac disease (Gerace 2017). Autoimmune effects on the central nervous system are also not uncommon. In celiac patients with neurological manifestations, almost 20% were found to have autoimmune antibodies known to interact with the brain, likely causing neurological damage and dysfunction (McKeon 2014).

Celiac Disease, Depression and Anxiety

A recent meta-analysis found significant correlations between a diagnosis of celiac disease, mood and anxiety disorders (Sharma 2021). In the study, celiac disease increased the incidence of:

• Depression by a factor of 1.6
• Dysthymia by a factor of 5.27
• Anxiety by a factor of 1.41
• Panic disorder by a factor of 4.64

The data shows a clear pattern of higher depression and anxiety problems for individuals with celiac disease.

And while some research suggests that a gluten-free diet can help resolve the symptoms of depression and anxiety, other research shows it isn’t always effective. A significant proportion of individuals diagnosed with celiac disease are unable to fully maintain a strict gluten-free diet, which could contribute to residual symptoms. While others have autoimmune or inflammatory components which do not completely resolve, requiring additional interventions. Identifying celiac disease in patients with mental health conditions can still require a comprehensive approach to fully address the underlying problems.

Celiac Disease and Eating Disorders

Another condition where I’ve commonly encountered undiagnosed celiac disease is in patients struggling with eating disorders. And the research bears this out. Patients with celiac disease are more likely to develop an eating disorder while patients with an eating disorder are also more likely to develop celiac disease (Nikniaz 2021).

Celiac disease itself can easily be confused with anorexia due to the similarity in symptoms. Patients lose weight and often have bloating and discomfort from food. In cases of anorexia, especially those that aren’t gaining weight with appropriate treatment or when gastrointestinal symptoms suggest the condition, screening for celiac disease is warranted. However, treatment needs to be approached judiciously, as restricting gluten in patients with anorexia should only be utilized in patients with an accurate celiac diagnosis.

Celiac Disease and Schizophrenia

Schizophrenia is a devastating mental health condition that can disrupt lives leading to life-long impairments. While a number of risk factors have been identified for the condition, celiac disease can also play a role. In fact, a recent meta-analysis concluded that the risk of schizophrenia was twice as high in patients with celiac disease (Wijarnpreecha 2018).

Studies on schizophrenia have found that a significant subset of patients, approximately one-third, have IgG anti-gliadin antibodies (Kelly 2022). These patients generally have higher levels of inflammation. Upon removal of gluten, this subset of schizophrenia patients often have both improvements in inflammatory levels and in schizophrenia symptoms.

Previous case reports have also documented complete remission of schizophrenia with a gluten-free diet in some individuals (Jansson 1984, De Santis 1997, Kraft 2009). From the data, and from my own experience, celiac disease should not be overlooked as a potential cause or contributing factor in schizophrenia.

Takeaway

Celiac disease can cause or contribute to mental health conditions. And the list above isn’t exhaustive. Data also links attention-deficit/hyperactivity disorder and autism with celiac disease (Niederhofer 2006, Butiwicka 2017). For any patient struggling with both a mental health condition and digestive symptoms, celiac disease should be considered. In other mental health conditions that are refractory to treatment, it can also be a potential factor, as many cases of celiac disease don’t present with classic gastrointestinal symptoms.

The mind and the body are connected. For too long, mainstream psychiatry has ignored this connection and focused on symptom management. Yet data continues to accrue showing a relationship between mental health and physical health. The more we evaluate all of the potential factors that disrupt this connection, the better our treatment outcomes.

Nutritional deficiencies, dietary factors, hormonal dysregulation, toxicities, chronic infections, genetic polymorphisms and psycho-social history can all play a part in an individual’s mental health status. Psychiatry Redefined was founded to teach this more individualized, research-based, whole-person approach for treating and resolving mental health conditions.