Classic ketogenic diet (and its modifications) - the therapy for epileptiform conditions caused by some defects of carbohydrate and fat metabolism. Part I. Ketogenic diet mechanisms of action
Ketogenic diet (KD) is a low carbohydrate diet that contains high amounts of fats and moderate amounts of proteins and includes vitamins, micro- and macroelements (particularly, calcium in combination with vitamin D). In a healthy human on traditional balanced diet, carbohydrates from food are being converted to glucose that provides energy for the central nervous system (CNS). KD contains little carbohydrates, therefore liver, to provide organism with energy, compensatory converts fat into fatty acids and then into ketone bodies acetoacetate, b-hydroxybutyrate, acetone as an alternative to glucose (ketogenesis). This results in ketosis - increased levels of ketone bodies in blood followed by their utilization in mitochondria of peripheral tissues and CNS (ketolysis). Simultaneously, a deep reprogramming of metabolic processes occurs resulting in therapeutic (in epilepsy and many neurodegenerative diseases) or negative (when fat metabolism defects or liver and kidney insufficiency are present) consequences. KD was initially used (frequently with therapeutic benefit) for the treatment of epileptiform conditions caused by defects in energy metabolism in children and later in adults (using lightened modifications with modestly increased levels of carbohydrates, proteins and medium-chain fatty acids). KD provides sufficient number of calories (matching patient’s height and age) to maintain normal body weight, necessary amount of protein and minimal amount of carbohydrates for organism growth and regeneration. KD is used successfully in patients with CNS glucose transport defects (GLUT-1), pyruvate dehydrogenase deficit, it provides benefits in obesity, type 2 diabetes, Parkinson’s and Alzheimer’s disease, lateral amyotrophic sclerosis, multiple sclerosis, stroke, traumas and brain malignancies, Classic KD is contraindicated in ketogenesis and ketolysis defects, liver insufficiency, kidney insufficiency, carnitine palmitoyltransferase I (mitochondrial fatty acid transporter) deficiency but its modifications are effective in some fat metabolism defects.