Eligible children will be randomized using computer generated random number tables in two groups: the intervention and the control arm. Both groups will undergo a baseline 4-week observation period, during which parents will be asked to maintain a daily seizure activity log; recording seizure type, duration and frequency. In the intervention arm, the children will start the modified Atkins diet after this 4-week baseline period. The control group will receive their normal diet with no dietetic input, and remain on the same on-going antiepileptic medication for the 3 months. Anti-epileptic medications will remain unchanged during the 3 month trial period in both groups, unless the change in AED regimen is medically indicated; e.g. drug side effects or status epilepticus; in which case standard therapy will be provided.