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The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used primarily to treat difficult-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than carbohydrates. Normally, the carbohydrates contained in food are converted into glucose, which is then transported around the body and is particularly important in fuelling brain-function. However, if there is very little carbohydrate in the diet, the liver converts fat into fatty acids and ketone bodies. The ketone bodies pass into the brain and replace glucose as an energy source. An elevated level of ketone bodies in the blood, a state known as ketosis, leads to a reduction in the frequency of epileptic seizures.〔 The original therapeutic diet for paediatric epilepsy provides just enough protein for body growth and repair, and sufficient calories〔 to maintain the correct weight for age and height. This classic ketogenic diet contains a 4:1 ratio by weight of fat to combined protein and carbohydrate. This is achieved by excluding high-carbohydrate foods such as starchy fruits and vegetables, bread, pasta, grains and sugar, while increasing the consumption of foods high in fat such as nuts, cream and butter.〔 Most dietary fat is made of molecules called long-chain triglycerides (LCTs). However, medium-chain triglycerides (MCTs)—made from fatty acids with shorter carbon chains than LCTs—are more ketogenic. A variant of the classic diet known as the MCT ketogenic diet uses a form of coconut oil, which is rich in MCTs, to provide around half the calories. As less overall fat is needed in this variant of the diet, a greater proportion of carbohydrate and protein can be consumed, allowing a greater variety of food choices.〔〔 The classic therapeutic ketogenic diet was developed for treatment of paediatric epilepsy in the 1920s and was widely used into the next decade, but its popularity waned with the introduction of effective anticonvulsant drugs. In the mid-1990s, Hollywood producer Jim Abrahams, whose son's severe epilepsy was effectively controlled by the diet, created the Charlie Foundation to promote it. Publicity included an appearance on NBC's ''Dateline'' programme and ''...First Do No Harm'' (1997), a made-for-television film starring Meryl Streep. The foundation sponsored a multicentre research study, the results of which—announced in 1996—marked the beginning of renewed scientific interest in the diet.〔 Almost half of children and young people with epilepsy who have tried some form of this diet saw the number of seizures drop by at least half, and the effect persists even after discontinuing the diet.〔 The most common adverse effect is constipation, affecting about 30% of patients—this was due to fluid restriction, which was once a feature of the diet, but this led to increased risk of kidney stones, and is no longer considered beneficial.〔〔 There is some evidence that adults with epilepsy may benefit from the diet, and that a less strict regimen, such as a modified Atkins diet, is similarly effective.〔 Clinical trials and studies in animal models (including ''C. elegans''〔) suggest that ketogenic diets provide neuroprotective and disease-modifying benefits for a number of adult neurodegenerative disorders.〔〔 As of 2012, there is limited clinical trial data in these areas, and, outside of paediatric epilepsy, use of the ketogenic diet remains at the research stage.〔〔〔 ==Epilepsy== Epilepsy is one of the most common neurological disorders after stroke,〔 and affects at least 50 million people worldwide.〔 It is diagnosed in a person having recurrent unprovoked seizures. These occur when cortical neurons fire excessively, hypersynchronously, or both, leading to temporary disruption of normal brain function. This might affect, for example, the muscles, the senses, consciousness, or a combination. A seizure can be focal (confined to one part of the brain) or generalised (spread widely throughout the brain and leading to a loss of consciousness). Epilepsy may occur for a variety of reasons; some forms have been classified into epileptic syndromes, most of which begin in childhood. Epilepsy is considered refractory (not yielding to treatment) when two or three anticonvulsant drugs have failed to control it. About 60% of patients will achieve control of their epilepsy with the first drug they use, whereas about 30% do not achieve control with drugs. When drugs fail, other options include epilepsy surgery, vagus nerve stimulation and the ketogenic diet.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ketogenic diet」の詳細全文を読む スポンサード リンク
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