According to experts in Britain a high-fat diet for children with severe epilepsy can dramatically reduce or prevent seizures; seizures are caused by bursts of electrical activity in the brain.
In new research by doctors at Great Ormond Street Children's Hospital it has been found that a high-fat, low-carbohydrate diet regime, known as a ketogenic diet, can reduce the number of fits suffered by children.
In the first randomised controlled trial to test the efficacy of the diet in children with drug-resistant forms of the condition, 145 children, aged between 2 and 16, who suffered daily seizures and had failed to respond to treatment with at least two anti-epileptic drugs, took part.
The diet has been around since the 1920s, it alters the body's metabolism by mimicking the effects of starvation - half of the group started the diet immediately while the others waited for three months.
The researchers say the number of seizures in the children on the diet fell to two-thirds of what they had been, but remained unchanged in those who had not yet started the diet; five children in the diet group saw a seizure reduction of more than 90%.
Some side-effects were experienced including constipation, vomiting, lack of energy and hunger.
While it remains unclear how the diet works it appears that ketones, produced from the breakdown of fat, helps to alleviate seizures.
Professor Helen Cross, a consultant in neurology at Great Ormond Street says the diet become unpopular because it was considered too difficult to sustain.
Parents involved say the first two weeks were difficult, but it helps if you can see the benefits from it.
Professor Cross says if the epilepsy is easily controlled on one medication she would not advocate the diet, but if at least two drugs have failed then it should be considered.
The researchers say that the diet should be recommended as an NHS treatment for children when drugs have failed to control their epilepsy.
The study is published in the Lancet Neurology journal.