LONDON -- A chemical imbalance in the brain affecting cell membranes may be at the heart of chronic fatigue syndrome, researchers suggest. The study, the first of its kind, also indicates that taking fish oil supplements might help.

Chronic fatigue syndrome (CFS) affects about 243,000 people of all ages in Britain. It causes a wide range of symptoms including muscle pain, memory loss, and severe exhaustion which can last many years and leave victims bed-ridden.

The fatigue is not like normal tiredness. It is a state of exhaustion.

Doctors have only recently started taking the illness seriously, and the mechanisms underlying the disorder are still not understood.

The new research from a team of London scientists involved a comparison between eight patients with CFS and the same number of healthy individuals.

The team reported its findings in the ***Acta Psychiatrica Scandinavica **** journal.

The findings indicate that phospholipid metabolism in the brain is abnormal in CFS sufferers, resulting in damage to nerve cells.

Phospholipids are special types of fats which are an essential component in cell membranes.

Certain fatty acids are thought to protect against the kind of harm identified by the research, helping to replenish and prevent the breakdown of phospholipids. Dr. Basant Puri, from Hammersmith Hospital, London, who led the research, said: "This study suggests that if patients with CFS take a high-EPA fatty acid supplement, then this should have a beneficial action on the chemical imbalances in the brain which we have identified."

EPA, found in fish oil supplements, influences the brain's chemical balance. It also plays a role in communication between cells and is the raw material for inflammatory prostaglandins -- short-lived hormones that influence sleep, mood and general well-being, DPA reported.

The scientists used a state-of-the-art scanning technique called cerebral proton magnetic resonance spectroscopy to look at the chemical activity within the brains of the volunteers. It showed significantly higher ratios of levels of two key chemicals in a region called the occipital cortex at the back of the brains of CFS patients.

CFS sufferers had higher levels of choline compared with levels of creatine. Choline is important for the controlling fat levels and nerve transmission, while creatine provides energy. The scientists said increased choline levels were known to be associated with abnormal membrane phospholipid metabolism.