What is the gut-brain axis?

The relationship between our gut and our brain has fascinated scientists and clinicians for decades. What was once thought to be a simple interaction is gradually unfolding into one of the most complex puzzles of the human body. When the term gut-brain axis is used, it refers to the interaction between our endocrine and nervous systems. The two systems communicate through biochemical signaling, often through microbiota, which play an important role in the function of our brain. Some of these functions include the regulation of anxiety, pain, cognition, and mood. Microbiota of the gut are largely influenced by dietary intake. In this context, the question of interest is whether the benefits of a gluten-free diet will alter our gut microbiota for the better, and in turn improve the functions of our brain to reduce anxiety, pain, and improve mood.

What are the benefits of a gluten-free diet for Depression?

A common belief is that gluten sensitivity only exists in those who are diagnosed with celiac disease. The old belief was that if you did not suffer from celiac disease, then gluten would not have an effect on you. However recent research has indicated that this may not be the case, and that gluten may be affecting you without you knowing it. The most recent developments in gastroenterology have found the existence of non-celiac gluten sensitivity, a pattern of symptoms exhibited by individuals who do not have celiac disease, but show distinct psychological symptoms when they include gluten in their diet. Those with non-celiac gluten sensitivity cannot tolerate gluten and have similar but milder symptoms to those with celiac disease, minus the intestinal damage.

Most people would tend to shrug this off as a minor finding, but when these research studies are examined a little closer, the details reveal a startling picture. For starters, a recent study in February of 2015 by Italian researchers demonstrated that as little as 5g of gluten per day could significantly increase symptoms of foggy mind and depression. The effects of gluten also included intestinal symptoms such as abdominal pain and bloating. While some might argue that these effects only take place after long-term gluten rich diets, the effects highlighted in the study didn’t take place over a year, or even a month, but rather over one week period. That’s right, the participants followed a one-week gluten free diet, followed by one week in which they were given only 5g of gluten. The resulting findings showed that even a period as short as one week could have a robust and measurable effect on both intestinal and psychological symptoms. None of the participants suffered from celiac disease, but still showed sensitivity to gluten. These findings are startling because they raise several questions about the extent to which our gluten rich diets are affecting us. Could the gluten in your diet be giving you symptoms of depression and clouded thought?

How does it relate to mental illnesses such as ADHD, depression, and bipolar disorder?

This is a very hot topic among researchers, as the relationship between the digestive system and mental illnesses is slowly unfolding. When looking at the evidence in patients with celiac disease, one can easily see that what we eat can have a large spectrum of psychological effects ranging from attention deficit disorder to schizophrenia. The exact mechanism of how these psychological disorders emerge is still unclear, however their existence is undeniable. It is predicted that perhaps gluten is responsible for causing imbalances in neurotransmitters, which then have an effect on our central nervous system. What we can be certain of is that even in those without celiac disease, gluten sensitivity has been related to psychological disorders, such as autism, schizophrenia and depression.

With regards to non-celiac gluten sensitivity, the majority of cases remain undiagnosed, so it is unknown what portion of the population are suffering from psychological symptoms due to it. Furthermore, from a quantitative rather than a qualitative standpoint, it is still unknown whether we all demonstrate a given threshold of gluten sensitivity. It is possible that gluten sensitivity affects us all, the difference being the amount that we can tolerate. If that proves to be the case, then perhaps making the switch to a gluten-free diet can benefit anyone experiencing excessive symptoms of psychological disorders such as ADHD, depression, and bipolar disorder. Perhaps it can help improve quality of life for even those who don’t know that the cause of their psychological distress is gluten. The only way to know with certainty is by removing gluten from our diets and examining the consequences, because if you never try, then you’ll never know.

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