Fish oils for treatment of major depression

According to new guidelines published in Psychotherapy and Psychosomatics the latest recommendation for the treatment of Major Depressive Disorder (MDD) is for the inclusion of omega-3 polyunsaturated fatty acids (n-3 PUFAs) as an 'adjunctive therapy'.

Major Depressive Disorder (MDD) affects ten percent of the population and is often cited as the leading cause of disability. There are a number of potential biological causes for MDD. Anti-depressant drugs only have limited effect and are associated with various adverse effects (see link for reference). The paper states, "Clinicians therefore need more efficacious and tolerable treatments supported by valid scientific evidence and reliable practice guidelines".

Depression and Omega 3

Evidence and experience using n-3 PUFAs as an alternative or adjunctive treatment for MDD has been generally known for some time, however, until now there have been no official guidelines for their use. In response, an advisory subcommittee were formed and following review of all the scientific papers have produced practice guidelines for prescribing n–3 PUFAs.

The n-3 PUFAs or Omega 3 Fatty Acids consist of two groups of molecules including the following:

  • eicosapentaenoic acid (EPA), and
  • docosahexaenoic acid (DHA)

The way in which they work has been investigated in a number of studies and a number of different mechanisms have been suggested. The models show how these molecules can affect nerve cells, the chemical flow between nerve cells (neurotransmitter dysregulation), and inflammation of the nerve cells.

Fish and cod liver oil are the usual natural sources of the EPA and DHA PUFAs. Non-marine options include flax seeds and walnuts. 

The optimal duration for supplementation with n–3 PUFA was not calculated. However, estimations calculated on the length of time needed for n–3 PUFAs to be incorporated into nerve cells in the brain, and for subsequent nerve cell effects and anti-inflammatory actions, the panel endorses a prescriptive guideline of at least 8 weeks. 

This is the first international research society consensus-based practice guideline for clinical use of n–3 PUFAs in treating MDD.

Many food types are now well established to be associated with mood, and there are a number identified biological models for how the gut and brain interact with each other. In her comment with regard to the relationship between yoghurt and depressionMiss Stephanie Moore, a clinical nutritionist with a background in psychotherapy is unsurprised by the findings. “There are many easy, daily practices that can quickly and effectively enhance the state of these highly influential gut bacteria and in turn improve inflammatory bowel problems and digestive discomfort. Anxiety, depression and other mental health problems may also be positively affected.”



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