Mental depression is common affecting 810percent of the population at any time.
Statistics show that the prevalence of major depression has increased and the age of onset has decreased in every decade during the 21st century in the Western World.
As a result anti-depressive medication is on the top list of social expenditure for drugs in many countries. But even if these drugs have proven very effective there is a need for the individual to take own responsibility for the disease, especially in the prevention of relapse after having ended the medical treatment.
Prevention must be based on psychotherapy to give the patient insight into which mechanisms that can lead to new depressive attacks and to recognise early symptoms of relapse.
But there may also be complementary ways of increasing the effects of non-pharmacological prevention, like dietary measures.
Serotonin regulates mode and awareness and malfunctions of the serotonergic system are common in depression, but also other psychiatric disorders.
Drugs sustaining the function of serotonin in the synapse or increasing the response at the receptor are used for treatment of depression (Prosac is one example). It seems that marine fatty acids increases the effects of the serotonergic system and may be used therapeutically as soft anti-depressive. Interestingly it seems that a lack of polyunsaturated fatty acids in the diet may lead to depression.
A dietary survey of 9 countries around the world clearly demonstrated higher prevalence of mental depression in populations not eating fish. In a recently published article US scientists found low contents of omega-3 fatty acids in mothers milk of women with depressive disease after delivery. Mothers without depression had significantly different values. People in Iceland do not have seasonal winter depression as the inhabitants of Canada have, probably due to the very different habits of seafood intake. People in Finland with a relatively frequent intake of fish have less frequent depression and significant lower risk of suicide compared to those not eating fish. Patients with severe depression have in general low levels of omega-3 fatty acids in the blood. So there may be every reason to think that marine omega-3 fatty acids could be important for prevention and even treatment of depression.
There have been three controlled clinical studies on the effects of treatment with marine omega-3 fatty acids on patients with depressive diseases. One study in 30 manic depressive patients from Boston clearly demonstrated that those given omega-3 fatty acids stayed in remission better compared to those given placebo. Positive effects were evident also for manic symptoms.
