The Impact of Omega-3 on Mental Health

One percent of the world's population has schizophrenia. At least 54 different genes with spontaneous mutations may make someone vulnerable to schizophrenia; then, a variety of environmental factors act on this vulnerability to initiate the symptoms. Schizophrenia is characterized by a consistent array of symptoms that are not expressed by every patient.

Most patients experience a prodromal phase, which is a period between the appearance of initial symptoms and the full development of the disorder, where they display nonspecific psychotic symptoms. This phase of transition of modest symptoms to major symptoms is of interest to neuroscientists because it might offer an opportunity for therapeutic intervention that might prevent the transition to a psychotic disorder. These individuals are defined as clinical high-risk (CHR); they have a 22 percent risk of developing psychosis in the first year after their initial diagnosis.

In addition to an array of genetic mutations that predispose someone to schizophrenia, a considerable body of evidence suggests that inflammation and oxidative stress play a critical role during the earliest stages of the disorder. The evidence is so compelling that many of the best animal models of schizophrenia are focused on the role of inflammation.

Current antipsychotic medications that affect dopamine function are inadequate in treating negative and cognitive symptoms and have serious and unpleasant side effects that discourage patients from taking their medications. We need better medications and interventions that can either delay or prevent the development of psychosis. Some recent studies have investigated dietary interventions that might defend against inflammation or oxidative stress.

Investigating the clinical benefits of omega-3 fatty acids

Attention has turned to the health benefits of dietary omega-3 fatty acids. There are two important omega-3 fatty acids: docosahexaenoic acid and eicosapentaenoic acid. They help to organize, and then resolve, our inflammatory response by regulating the levels of inflammatory proteins.

Intervening at the prodromal stage with dietary omega-3 fatty acids has been considered, however, the few initial studies did not produce significant clinical benefits.

A recent study investigated the clinical benefits of omega-3 fatty acids in a large group of clinically high-risk patients. The intent was to prevent the onset of psychosis in high-risk participants who had little or no exposure to antipsychotic medication that might alter the level of inflammatory proteins. The CHR patients had elevated levels of inflammatory proteins in their blood prior to starting the diet containing omega-3 fatty acids.

Six and twelve months after starting the diet rich in omega-3 fatty acids, plasma levels of inflammatory proteins decreased significantly. This outcome was like other studies that have demonstrated the anti-inflammatory effects of omega-3 fatty acids in patients with neurodegenerative disorders, cerebrovascular ischemic disorders, and psychiatric disorders such as depression and bipolar disorder. However, despite the reduction in blood biomarkers of inflammation, the patients demonstrated no significant clinical benefits. Diets high in omega-3 fatty acids are generally beneficial; unfortunately, they are not capable of altering the progression of psychotic symptoms during the prodromal phase.