Fish oil and depression

It seems that everyone is talking about Omega 3 these days and the positive effect that fish oil can have on a whole range of health problems. The media continue to report on how fish oil can protect against heart disease, reduce inflammation, boost the immune system and how it can improve brain function in general so it should come as no surprise to any of us that the evidence also shows that fish oil can have a dramatic effect on depression and other mood related disorders. Why?

Some of us will have already heard that fish oil is brain food and in a way, that’s exactly what it is. Not only is the brain largely composed of fat, it needs the Omega 3 fatty acids found in fish oil in order to work properly too. Interestingly, people who are suffering from depression, ADHD, Alzheimer’s disease and other brain-related conditions have been found to have low concentrations of the essential Omega 3 fatty acids in their blood, particularly Eicosapentaenoic acid or EPA and perhaps this is no coincidence.

No one really knows the exact mechanisms involved or how it works but the indications are that EPA thins the blood and helps it to flow more efficiently to the brain, enhances inter neural connectivity, increases serotonin levels, reduces inflammation, improves concentration and memory and even has a mood elevating effect. Consequently, it stands to reason that supplementing with fish oil might alleviate symptoms of depression and this is just what researchers have been finding out.

What the research saysÂ…

A Harvard study led by Dr Andrew Stoll in 1999 reported that fish oil can dramatically improve symptoms of Bipolar disorder (manic depression). Bipolar disorder is a type of depression manifesting itself as repeated episodes of depression and mania or both and it can have a devastating effect on the life of the individual and their loved ones. In Stoll’s study, 30 bipolar patients with a history of relapses were given either fish oil or a placebo in the form of Olive oil. The trial was supposed to last for 9 months but was stopped after 4 months due to the dramatic results of the fish oil group who were able to reduce their symptoms of depression and stay in remission significantly longer than the placebo group.

Then in 2002 researchers Peet and Horrobin tested the antidepressant effect of ethyl EPA, a particularly concentrated form of EPA, and found that a dose of 1 gram daily was effective against depression. Participants were assigned either to the fish oil group or the placebo group and given various doses of fish oil daily for 12 weeks. At the end of the trial, those taking 1 gram of fish oil showed a significant improvement over those in the placebo group and the conclusion was that this dose was particularly effective in treating people with persistent depression.

Yet another study by Puri et al involved giving EPA in addition to normal medication to a suicidal male patient suffering from severe depression. Not only was there a cessation of suicidal ideation and an improvement in all the symptoms of depression, but brain scans carried out before and at the end of the trial indicated structural changes to the brain after taking EPA. This study also suggested that EPA might enhance the efficacy of other medication for depression.

Other studies have revealed that there is a higher incidence of postnatal depression in countries with a lower level of fish consumption. This makes a lot of sense when we consider that Omega 3 fatty acids are particularly important during pregnancy and in the first few years of a child’s life when the brain is developing very rapidly and if the mother doesn’t get enough fatty acids whilst pregnant, she can find her supplies depleted as they are transferred to baby.

Here in the UK, the Durham trials are consistently reporting on the positive effect that fish oil can have on behaviour, concentration and learning in the classroom and an Australian study led by researcher Natalie Sinn even reported that fish oil was more effective than Ritalin for Attention Deficit Hyperactivity Disorder or ADHD.


It would be reasonable then to conclude that a lack of Omega 3 fatty acids in the diet or perhaps even a higher than normal requirement for Omega 3 fatty acids can result in low fatty acid concentrations in the brain, which of course might increase the risk of depression and other related disorders. Depression can affect any one of us at any time, it is indiscriminate of age, background or gender and the numbers are increasing year after year.

Could it be that an overall reduction in consumption of fish and therefore Omega 3 fatty acids might be contributing in some way to a rise in cases of depression? The evidence isn’t conclusive but the indications are that fatty acids certainly have a role to play in the prevention and treatment of all kinds of depression and mood related disorders. Research in this area is growing rapidly and no doubt we will be hearing a lot more about the benefits of Omega 3 and EPA in the future. In the meantime, fish oil is a safe and convenient supplement that can be taken by everyone to improve health in general.