POWERFUL new evidence shows that children using a dietary supplement pioneered in the North-East are making huge advances, it was revealed last night.

Scans on youngsters in London, aged between eight and 13, showed their brains underwent three years' worth of development in only three months.

The results support Durham County Council's decision to give thousands of children fish oil. The new study says the supplements have a dramatic effect on pupils, improving reading, concentration, problem-solving and memory.

The latest evidence came after brain scans were carried out at St George's Hospital, in London. They showed a biochemical indicator of brain development called N-acetylaspartate (NAA), higher levels of which correspond to more nerve fibres growing in the brain.

The research was done by Professor Basant Puri, from Imperial College London, who worked with Dr Madeleine Portwood when similar trials began in the North-East.

There have been criticisms of the North-East study, suggesting it is not as effective as supporters claim. But Dr Portwood, a senior educational psychologist with Durham County Council, said the London results reinforced its findings.

She said: "In 2001, we conducted the biggest-ever clinical trial in the world by giving primary-age children fatty acid supplements.

"Professor Puri's recent study is showing that you can measure changes in brain cells. This is adding further evidence to the idea that fish oil can enhance performance.

The recent study gives much better weight to our findings that the structure of the brain can be affected by fish oils."

Dr Portwood said the programme in the region was ongoing. More than 3,000 year 11 pupils take capsules to help them concentrate on GCSE revision.

She is also carrying out research on primary school pupils in Middlesbrough and 69 primary-age autistic youngsters from Durham and Sunderland.

In December, she published a report into trials with three-year-olds in County Durham, whose language skills had developed by nine months during the five-month programme.

Children in the London study were given a supplement called VegEPA, which contains omega-3 and omega-6 essential fatty acids, for three months and encouraged to cut down on fatty snacks and fizzy drinks and be more active.

Tests showed an increase in reading age of well over a year, handwriting became neater and more accurate, and they paid more attention in class.

In one measurement of concentration, three children scored perfect results.

Prof Puri said: "The results were astonishing. In three months, you might expect to see a small NAA increase, but we saw as much growth as you would normally see in three years.

"For all the children, there was a marked change, but in the three boys, there was a massive increase in NAA."

The growth appeared to be spread throughout the cerebral cortex, the part of the brain that deals with thinking.

Imaging expert Professor Kishore Bhakoo, from the Medical Research Council's Clinical Science Centre, said the results had implications for the debate on junk food.

Prof Puri, who wants to repeat the experiment with a larger number of children, said: "It does make you think about education and whether we should be giving all children these supplements."

North-East mother Kelly Parkin backed the findings. Until a year ago, her six-year-old daughter, Catherine, was taking fish oil supplements, having started the treatment as a four-year-old, but it became too expensive at £10 a bottle.

Mrs Parkin, of Birch Avenue, Shildon, County Durham, said: "I would have liked to have kept her on them. We noticed a difference in her concentration as soon as we took her off them.

"She cannot seem to sit for five minutes, which is what it was like before." Prof Puri's work is to feature in a Channel 5 documentary on Thursday, Mind the Fat: Does Fast Food Slow Kids?