ONE day last year Anne logged on to the Internet and as usual went straight to the schizophrenia forum. What she read there has, she claims, transformed her life and that of her 40-year-old schizophrenic son. The article described how researchers at the University of Sheffield believe the key to treating schizophrenia may be found in fish oil.

Anne put her son, who was already taking the schizophrenia drugs Zyprexa and Lithium, on high doses of fish oil. Since then he has improved daily.

"He has been homebound for years," she told fellow Internet surfers. "He is now fishing, hitting golf balls in the yard and reading the sports page."

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Before long other benefits emerged, she says. A few weeks after taking the oil her son's doctor was confident enough about his progress to lower the dosage of his other drugs and, "he is now doing even better".

Anne's experience caused a stir on the schizophrenia web site. Over recent months, a flurry of e-mails have passed between schizophrenia sufferers and their families about the benefits of fish oil. If other families experience the same remarkable changes the effect on the NHS, as well as thousands of sufferers will be dramatic.

Each year the NHS spends pounds 810m on treating Britain's schizophrenics. They are the third most costly group of patients to the NHS, after learning disability and stroke victims. Over pounds 32 million is spent on drugs like the anti-psychotics used to control the most disturbing schizophrenic symptoms such as hallucinations, delusions and voices*.

Now psychiatrist Dr Malcolm Peet and his team at Sheffield believe they have found a treatment which is easily obtainable and at a fraction of the cost of drug therapies.

So far two studies have shown that patients given high doses of fish oil in addition to their usual drugs have seen symptoms improve by more than a quarter. In September last year, the researchers at Sheffield took the investigation a stage further, using several different formulations of EPA, a type of fish oil, and 75 patients - the research should be completed by the summer.

Dr Peet is pleased with the results so far but emphasises that the work is at an early stage. On no account must patients stop taking their medication and rely on fish oil, he says. "We have no proof to support a sole treatment approach," he says.

One hundred and fifty miles away in Hammersmith Hospital London, one man has watched with astonishment the remarkable transformation of a 31- year-old schizophrenic after treatment with EPA - a change all the more remarkable because the patient had never undergone conventional drug treatment for his condition.

Like Dr Peet, Basant Puri, consultant psychiatrist at Hammersmith hospital, was aware of studies linking schizophrenia with a depletion of certain fatty acids. But studies were hindered by the fact that most schizophrenics receive drug treatments of one form or another. As a result it was hard for researchers to have a clear picture of the effect of substances like EPA.

"The ideal is to have patients who are drug naive", Dr Puri explains. "I came across a patient who had refused medication and, after I explained the hypothesis to him, he was keen to try the fish oil."

Only six weeks into treatment and Dr Puri and his patient were amazed at the improvements: "I have never seen a patient get better so quickly."

The man had suffered hallucinations and was anxious and withdrawn when he arrived at Dr Puri's clinic. He had been diagnosed as a schizophrenic three years before but had only ever taken one tablet of the drug sulpiride - he refused to take any more after experiencing side-effects.

After a daily dose of EPA, "he is now up and about and trying to pursue an Open University degree course," Dr Puri says. He is convinced that the man's recovery is no fluke. The patient's illness had never been episodic and his symptoms had been constant for two years. Also he had been involved with several research studies and so was unlikely to have improved as a result of extra attention he got from the team.

Schizophrenia is the most feared and misunderstood mental illness. In the eyes of the public it turns its 250,000 British sufferers from Dr Jekylls into Mr Hydes, ordinary men and women into killers. Ill-informed press coverage has demonised sufferers and fuelled public fears about the condition.

The community care reforms have been condemned for releasing vulnerable and sometimes volatile or dangerous individuals into the community without proper support. Fragile support networks have broken down and led to a number of well-publicised tragedies.

In the 1950s, two French doctors discovered the first anti-psychotic drug, Chlorpromazine, which revolutionised the treatment of severe mental illness and allowed people to be treated in the community.

In the last 40 years doctors have learned to transplant hearts and make babies in tubes, but there has been surprisingly little progress in drug therapies during that time, says Dr Peet.

The first drug was quickly followed by others that act in much the same way, by blocking messages to receptors in the brain. Even the latest versions produce a range of distressing and damaging side effects.

While they work to reduce hallucinations and delusions they do nothing for the apathy and emotional bluntness experienced by patients, says Dr Peet. And large doses can make these symptoms worse.

New kids on the block, such as Clozapine, produce fewer side effects but have other problems. Schizophrenics on anti-psychotic drugs can also develop the symptoms associated with Parkinsons disease and experience stiff muscles, a shuffling walk and limited facial movements.

About a fifth of patients on long-term treatment develop a condition called tardive dyskinesia, with sudden involuntary facial or body movements and difficulty swallowing and walking. Long-term drug treatment exacerbates the condition and there is evidence that symptoms continue even after drug treatment stops, leaving patients, "effectively brain damaged".

The fish oil story began five years ago after Dr Peet noticed that a number of studies found evidence that due to a genetic flaw, schizophrenics' cell membranes lack certain polyunsaturated fatty acids which affects the development of the brain.

Inspired by this work, Dr Peet's team conducted a pilot study in 1993 of 20 patients. The results were encouraging.

They indicated that the more polyunsaturated fatty acids a patient consumed the fewer symptoms they had.

Determined to test the theory further, a year later the Sheffield team conducted a trial to see if supplementing patients' diets with high doses of fatty acids would repair the damage and affect the course and outcome of the condition.

In a double blind trial that demands neither side knows what they are administering or receiving, 45 patients already on anti-psychotics and still exhibiting symptoms took one of two types of fish oil, EPA or DHA, or a corn oil placebo. The results were startling. The team found symptoms reduced by a quarter in those who took EPA.

Snake oil, fish oil, what's the difference some asked? Dr Peet admits to having encountered initial scepticism from psychiatrists but a great deal of interest by nutritionists.

If fish oil proves to be the key to a new dawn in the treatment of schizophrenia then Dr Peet will make an unconventional hero. With his shoulder-length grey hair and snappy suits he is a long way from the lab-coated boffin stereotype.

Dr Peet laughs at the idea that he is a radical. "I am conventional in my clinical practice, I can assure you," he says.

Based on results so far, people suffering from schizophrenia could do worse than take concentrated fish oil supplements readily available in pharmacies and health food shops.

While not the pure form used by researchers they do contain large amounts of EPA and the evidence so far suggests it would be beneficial, he says. With the scientist's caution, he adds: "Let me put it another way - if I were a schizophrenic I would be taking it."

If Dr Peet is right then for many, distressing side effects could be a thing of the past.

The shame is that people suffering from schizophrenia have had to wait over forty years for something that they could have bought in the local chemist.

* Costs of Schizophrenia, Martin Knapp, British Journal of Psychiatry (1997), 171, 509-518.