Gluten-free diet can improve depression and behavioral problems in adolescents
As the authors of this study published in the journal BMC Psychiatry observe:
"Coeliac disease in adolescents has been associated with an increased prevalence of depressive and disruptive behavioural disorders, particularly in the phase before diet treatment."
We are equally concerned with the 'non-celiac' aspects of gluten sensitivity. Gluten related inflammation in the brain can manifest as a host of cognitive, emotional and neurodegenerative disorders in the absence of intestinal manifestations. This is often referred to as "silent celiac disease":"Coeliac disease is an under-diagnosed autoimmune type of gastrointestinal disorder resulting from gluten ingestion in genetically susceptible individuals. Non-specific symptoms such as fatigue and dyspepsia are common, but the disease may also be clinically silent."They further note that:
""Depressive symptoms and disorders are common among adult patients with coeliac disease, and depressive and disruptive behavioural disorders are highly common also among adolescents, particularly in the phase before diet treatment. Recently 73% of patients with untreated coeliac disease – but only 7% of patients adhering to a gluten-free diet – were reported to have cerebral blood flow abnormalities similar to those among patients with depressive disorders."
Their data revealed abnormalities in tryptophan assimilation (tryptophan is the amino acid precursor to serotonin) and prolactin levels in adolescents with celiac disease and depression prior to treatment. Consequently...
"A significant decrease in psychiatric symptoms was found at 3 months on a gluten-free diet compared to patients' baseline condition, coinciding with significantly decreased coeliac disease activity..."
They also make a fascinating observation that links gluten sensitivity, inflammation, and the serotonergic aspect of depression unrelated to malabsorption:
"...increased production of interferon-γ (IFN-γ), known to be the predominant cytokine produced by gluten-specific T-cells in active coeliac disease, can suppress serotonin function both directly and indirectly by enhancing tryptophan and serotonin turnover...even without malabsorption."
To diagnose gluten sensitivity in the absence of celiac disease the gluten gene sensitivity test is the most reliable method for a number of reasons.