 About 20 % of children on the ketogenic diet achieve freedom from seizures , and many are able to reduce the use of anticonvulsant drugs or eliminate them altogether . Commonly , at around two years on the diet , or after six months of being seizure @-@ free , the diet may be gradually discontinued over two or three months . This is done by lowering the ketogenic ratio until urinary ketosis is no longer detected , and then lifting all calorie restrictions . This timing and method of discontinuation mimics that of anticonvulsant drug therapy in children , where the child has become seizure free . When the diet is required to treat certain metabolic diseases , the duration will be longer . The total diet duration is up to the treating ketogenic diet team and parents ; durations up to 12 years have been studied and found beneficial . 
