The diet was extremely beneficial to those who had suffered fits every day despite medication, with the number of seizures in their case actually reducing to one third after following the diet.

According to the researchers the diet works by modifying the body's metabolism by mimicking the effects of starvation.

This is the first of its kind trial that has compared the diet with routine care, and now the researchers have called for this diet to be more widely available on the NHS.

While the exact working of this diet is not clearly known, it is hypothesized that ketones, produced from the breakdown of fat, aid in lessening the seizures.

The study recruited 145 children between 2-16 years of age who had failed to respond to treatment with at least two anti-epileptic drugs. All these children were given specific diet having high fat content, low levels of carbohydrates and with controlled amounts of protein. While 50% started the diet immediately, the other 50% waited for three months.

The results indicated a two-third decrease in the number of seizures in the children on the diet, but it did not have any impact in those who had not started the diet. In fact, there was a 90% reduction in seizure in five children in the diet group. However, some side-effects like constipation, vomiting, lack of energy and hunger were also observed.

According to professor Helen Cross, study leader and consultant in neurology at Great Ormond Street Hospital in London, the diet has been in existence since the 1920s, but not many prefer it as it is a little too difficult to follow.

"The parents say the first two weeks are quite difficult, but then it becomes much easier because you can make foods in bulk, and it especially helps if you can see the benefits from it," BBC quoted her as saying.

She also said that the diet has been recommended by national guidelines as a viable treatment option, but it is not available easily due to a lack of dieticians.

"The results of this trial add valuable information to what is already known about the diet, presenting evidence that it works for some children with drug-resistant epilepsy. In addition to this, however, we also recognise that the ketogenic diet is not without its side-effects, and that the risks and benefits should be considered before prescribing, as with drug treatment," said a spokesperson for Epilepsy Action.

Cross was quite hopeful of the fact that the results would encourage a mauch larger inclusion of the diet in the management of children with drug-resistant epilepsy.

The study was reported in the Lancet Neurology.

From the May 12, 2008, Prepared Foods e-Flash