Depression: Discover how an incredible fatty acid could be the breakthrough you've been waiting for

Almost three million Britons suffer from depression battling with tearfulness, low self esteem, anxiety, fatigue, lack of interest in usual activities, feelings that life is not worth living and, at worst, suicidal thoughts.

Depression comes in many forms and has a wide range of causes. Most familiar is the kind caused by stressful situations such as bereavement, divorce or losing a job. Postnatal depression, or baby blues, and seasonal affective disorder (SAD) both have their roots in hormonal changes in the body. Diseases such as cancer and rheumatoid arthritis also cause changes in body chemistry that can lead to depression (quite apart from the worry of having the illness).

But for many cases of clinical depression, and for bipolar disorder, where periods of depression alternate with episodes of hyperactivity or mania, finding a clear cause often proves impossible.

While doctors often find it hard to see beyond antidepressant drugs, the latest cutting-edge research findings have revealed that an essential fatty acid naturally found in fish oils can have remarkable results in combating depression.

Now, you may be thinking that fish oils as a treatment for depression is hardly ground-breaking news (Lancet 1998; 351: 1213). However, the new research shows that only one of the two main fatty acids present in fish oil is beneficial against the condition and that taking the two together could even negate these positive effects making it vital that the right one is taken.

The shocking risks and side effects of antidepressant drugs

It has been estimated that only half of depressed patients seek help from their doctor, half who do so are correctly diagnosed, half of those receive treatment and only half who get it stick to it this means fewer than one in ten depressed people are actually taking antidepressant medication (BMJ 2005: 332: 800-801). 

That may be no bad thing, since antidepressants come with a high risk of side effects, some fatal. For instance, the drug Seroxat may increase the risk of suicide six-fold. In fact, every antidepressant licensed since 1987 has been associated with a higher risk of suicide (BMJ 2006; 333: 92-5).

There are three main kinds of antidepressants, all of which have their own problems. The oldest kind, called tricyclics, such as amitriptyline (Tryptizol) and imipramine (Tofranil) commonly cause drowsiness, dry mouth, constipation, sweating, dizziness and blurred vision.

Selective serotonin re-uptake inhibitors, or SSRIs, include fluoxetine (Prozac) and paroxetine (Seroxat) and can cause headaches, nervousness, insomnia, anxiety, nausea, diarrhoea and reduced libido. They are also addictive and cause unpleasant withdrawal symptoms such as constant agitation, sleeplessness and nightmares.

Finally, the monoamine oxidase inhibitors (MAOIs), such as phenelzine (Nardil) and tranylcypromine sulphate (Parnate), have less side effects but can cause a dangerous rise in blood pressure if taken with foods containing the amino acid tyramine, such as cheese, or with decongestants or antihistamines.

Fish oil fatty acid beats depression, but works best alone

While antidepressants may not be the answer, leaving depression untreated certainly isnt. This is where fish oil comes in. It contains two omega-3 essential fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Fatty acids form the building blocks of tiny membranes in your brain cells and omega-3s make these membranes more permeable so that neurotransmitters (your brains chemical messengers) can pass through them more easily.

The recent research findings have shown that it is only EPA that has depression-relieving properties and DHA may actually compete with EPA for binding sites in brain cell membranes and so reduce its effectiveness (Am J Psychiatry 2003; 160(5): 996-998).

Fortunately a number of supplements are now available that contain at least 90 per cent pure EPA and these have proved far more effective in treating depression than ordinary fish oil. Better still, just 1 gram of EPA a day appears to be the optimum dose, so avoiding the need to take large amounts (up to 10g a day) of fish oil, which some people find upsets their digestion.

Dr Basant Puri, a consultant psychiatrist at Londons Imperial College Hospital, firmly believes that a lack of essential fatty acids in modern diets is at the root of the current depression epidemic.

One of Dr Puris first successes with EPA was in treating a young man who had been suffering from major depression for seven years. After seeing countless doctors and being prescribed virtually every psychiatric drug available, he was in the depths of despair and suicidal. This kind of long-term depression is notoriously resistant to treatment, yet EPA brought about a dramatic improvement in just a matter of weeks and after nine months the patient was a totally different person, full of energy, confidence and optimism (Int J Clin Pract 2001; 55(8): 560-563).

EPA succeeds where antidepressant drugs fail, even for bipolar depression

Dr Puris patient was not an isolated case, as Dr Malcolm Peet and his colleagues found from a double-blind clinical trial involving 70 patients with persistent depression despite ongoing drug treatment (Arch Gen Psychiatry 2002; 59(10): 872-873).

After twelve weeks, 69 per cent of the patients taking EPA reported a better than 50 percent improvement in their symptoms, compared with 25 percent of the placebo group. This compares well with the general success rates of conventional antidepressants. The researchers concluded that 1 gram of EPA daily is an effective treatment for depressed patients who do not respond to drug therapy.

EPA is also successful in treating the depressive phase of bipolar disorder (manic depression). At Harvard University in the US, Dr Andrew Stoll was the first to show just how effective fish oils can be in stabilising mood swings in bipolar patients (Arch Gen Psychiatry 1999; 56: 407-412).

Recently, a double-blind clinical trial at the Institute of Psychiatry in London has identified EPA as an effective and well-tolerated treatment for bipolar depression. After taking 1g of EPA daily for 12 weeks, patients scored significantly better in a range of depression-rating tests than the placebo group. No further advantage was found in increasing the dose to 2g a day (Brit J Psychiatry 2006; 188: 46-50).

What to take for best results

The recommended dosage is 500mg to 600mg of EPA taken twice a day. No side effects have been reported with EPA, but pregnant and breastfeeding women and people on blood-thinning medications are advised to check with their doctor before using it.