Does Gluten Impact Brain Function?

In recent years, extensive research has been carried out, exploring the impact that consuming gluten can have on the body. Many people are aware that gluten can trigger digestive issues and an immune response in people with sensitivity or a gluten-related disorder, such as coeliac disease. This primarily manifests through gastrointestinal symptoms, with some of the most common examples including bloating, diarrhoea, constipation, abdominal pain and malabsorption.

However, one topic that scientists are increasingly interested in is whether or not gluten has an impact on brain function. There is clear evidence that some people with gluten-related disorders experience cognitive impairment after ingesting gluten, but how widespread is this and are these symptoms limited to people with these conditions? In this blog post, we explore the impact of gluten on brain function, taking a critical look at the available evidence.

Gluten and the Brain

The full effects of gluten on the brain are still poorly understood, but there is sufficient evidence out there to connect issues like gluten sensitivity and coeliac disease with neurological issues. For example, a 2019 study of recently diagnosed coeliac patients found that 12% of participants had persistent sensory problems, while 24% demonstrated gait instability. In total, 47% had abnormal results from magnetic resonance spectroscopy of the cerebellum, which is part of the brain that helps with attention, regulation of motor movements, coordination of gait and control of balance.

Several studies, referenced later in this post, draw a link between gluten intake and the development of neurological diseases or conditions. It has been hypothesised that this could be related to the presence of elevated tissue transglutaminase-2 (tTG2) autoantibodies – a relevant marker used for coeliac disease diagnosis.

Examples of Gluten Impacting Brain Function

Some of the most common examples of suspected or proven links between gluten consumption and impaired cognitive function in susceptible people are outlined in the sections that follow.

Clouding of Consciousness

The term clouding of consciousness is used to describe a state of lowered awareness and focus. Sometimes known as “brain fog”, people suffering from clouding of consciousness may experience an impaired ability to think carefully, solve problems and concentrate. They may also feel confusion, a kind of mental fatigue and a generalised haziness. On top of this, brain fog can also lead to memory issues and a lack of awareness of surroundings.

This kind of brain fog is one of the most common symptoms of coeliac disease and non-coeliac gluten sensitivity. In fact, in one survey of people who predominantly have coeliac disease, 90% of participants reported experiencing brain fog. The prevalence of this symptom is so high that it has even earned its own names. In the scientific community, it tends to be called gluten-induced neurocognitive impairment. It is also colloquially known as “coeliac fog”.

Interestingly, brain fog is also reported by a number of people who do not have coeliac disease, but who have a non-coeliac gluten sensitivity, or a suspected gluten intolerance of some kind. Some people also report brain fog after eating gluten, despite having tested negatively for coeliac disease and not meeting the requirements for gluten sensitivity. This suggests that clouding of consciousness is not necessarily a symptom that is limited to people who have coeliac disease.

Gluten Ataxia

Gluten ataxia is an autoimmune disorder, triggered by the consumption of gluten in people who are genetically susceptible. An article published by Coeliac UK explains that gluten ataxia is a neurological condition that can manifest even in situations where gluten consumption has not caused damage to the gut. People may experience gluten ataxia alongside conventional gastrointestinal symptoms, or without those more common stomach-related symptoms.

Although it is a rare condition, it is also the most common neurological manifestation of gluten-related disorders, aside from brain fog. Essentially, it is caused by the immune system attacking the central nervous system in response to the presence of gluten within the body. Some of the common symptoms include difficulty with speaking, gait and balance. People may also have problems with eye movements, or using their hands and fingers.

The primary treatment for gluten ataxia is to immediately cease eating gluten permanently. The faster this treatment measure is implemented, the better long-term outcomes are likely to be. People experiencing gluten ataxia can usually expect fairly rapid improvement in their symptoms if they are able to maintain a strict gluten-free diet.

Brain Inflammation

A scientific study published in 2022 explores the relationship between gluten consumption, tTG2 antibodies and the impact on the microbiota-gut-brain axis. In the study, it is explained that the inflammatory effects associated with gluten consumption are not always restricted to the gastrointestinal system. This is in-keeping with other studies and anecdotal reports, which have linked gluten consumption with inflammation of the brain.

Indeed, the study explains that the increased permeability of the intestines after inflammation caused by gluten makes it easier for bacteria and toxins to make their way into the bloodstream. This means the bacteria or the toxins may eventually be able to make their way to the central nervous system too.

The author concludes that there is a possibility the inflammation caused by gluten can lead to loss of integrity of the blood-brain barrier (BBB). A connection is also made between BBB permeability and a whole host of other neurological conditions and mood disorders, including depression, anxiety, and schizophrenia, but more research is needed.

Peripheral Neuropathy

Put simply, peripheral neuropathy is a term used to describe a variety of conditions that stem from damage to the nerves that carry messages to and from the brain and spinal cord. Over the years, a number of researchers have found a link between gluten intolerance or coeliac disease and the development of peripheral neuropathy.

For instance, a 2019 study found that peripheral neuropathy was the second most common of the neurological manifestations explored, with only gluten ataxia being more common. That study also found that a strict gluten-free diet was an effective first-line treatment for these various neurological disorders stemming from gluten-related disorders, with the majority of patients adhering to the diet seeing clear improvement after 12 months.

It should be noted that more research is still required to determine precisely how strong the link between gluten consumption and peripheral neuropathy is. To date, most studies have focused on patients who are already experiencing symptoms, who also already have a diagnosis of coeliac disease or gluten sensitivity.

Final Thoughts

In addition to the conditions outlined, there are small snippets of evidence indicating that gluten may contribute to either the development or worsening of symptoms in some people with attention deficit disorder and even some forms of dementia, especially in people with gluten sensitivity or coeliac disease. However, research on these topics is limited and is often considered to be controversial, so more studies are required to draw firm conclusions.

Gluten is safe to consume for most people, although gluten-free diets are becoming more popular. Most of the neurological effects of gluten appear to be limited to people who have either coeliac disease or a gluten intolerance. With that being said, it should be noted that both of these conditions are on the rise and are also under-diagnosed, meaning a person could have a sensitivity to gluten without yet being formally diagnosed with a disorder.