By Yam Cher Seng

HAVE we been fishing in all the wrong places for the magic bullet for depression? Have scientists been turning a blind eye to a well-known substance that works well for other diseases and conditions? Now, their focus appears to be widening.

After years of being bombarded by industrial-strength pharmaceuticals and toxic salts, people with depression could possibly look forward to a kinder and gentler treatment.

The association of omega-3 fatty acids as an antidepressant stems from a clutch of epidemiological studies, which established that high fish consuming nations such as Japan, Korea and Taiwan are linked with lower rates of depression. We eat far greater amounts of other damaging fats. In addition, depression is now occurring more commonly in younger persons. A healthy diet should provide for at least five grams daily of essential fatty acids, divided between omega-3 and omega-6.

Omega-3 fatty acids are polyunsaturated fatty acids considered essential because they cannot be synthesised by the human body. The two active ingredients of omega-3 fish oil are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Dietary fish and fish oil supplements are a direct source of EPA and DHA.

Omega-3 fatty acids and mental health

Although best known for cardiovascular benefits, new findings indicate the influence of omega-3 fatty acids in mental health, particularly EPA. Therefore, it is important to obtain an omega-3 supplement that contains more EPA than DHA. The fish oil should also provide a minimum of 60 per cent concentration of EPA & DHA, and has been molecular distilled to be contaminant-free.

Dr Hibbeln published a study in the Lancet (2002) that showed mothers selectively transfer DHA to their foetuses to support the optimal development of brain cells during pregnancy. If they don't receive enough, they run the risk of developing severe post-partum depression (after delivery). Thus, omega-3 fatty acids consumption is associated with lower risk of depression and higher mental health status.

It was found that depression isn't the only disease that may affect a person's levels of omega-3 fatty acids in the brain. Those who have been diagnosed with cardiovascular disease and other conditions associated with depression, have low levels of omega-3 fatty acids in their blood, too.

The study shows that those who only took one gramme of omega-3 fatty acid for 12 weeks experienced improvements akin to those given the inactive drug, in all the measurable aspects of depression, including sadness, anxiety, low sexual drive, sleeping problems and suicidal tendencies. These exciting new findings are not entirely surprising when one considers that the brain itself is 60 per cent fats and that one-third of all fatty acids is of the polyunsaturated variety.

In addition to changing serotonin and dopamine levels and functioning, omega-3 deficiencies are known to compromise the blood-brain barrier, which normally protects the brain from unwanted matter gaining access. Omega-3 deficiency can also decrease normal blood flow to the brain and causes a 35 per cent reduction in brain phosphatidylserine (PS) levels. This is of relevance when considering that PS has documented antidepressant activity in humans.

Patients with depression have 35 per cent less DHA in fat storage cells versus healthy people. DHA is found in high levels in the cells of the central nervous system (neurons).