Ketogenic diet

The ketogenic diet is a treatment for epilepsy that relies on inducing a state of ketosis. The diet prescribes foods high in fat, and heavily restricts carbohydrate intake. As fats become the body's primary source of metabolic energy, ketones accumulate in the brain, which can alleviate epileptic symptoms. The diet is more effective in children than adults, particularly when anticonvulsant drug therapy is ineffective (20%-30% of patients) or contraindicated.

The diet provides 3-4 grams of fat for every 1 gram of carbohydrate, calling for such foods as high-triglyceride dairy products (butter, cream, mayonnaise) and peanut butter. Carbohydrates, found in breads and starches, are eliminated from the diet, and liquid intake is often restricted as well in order to aid ketone accumulation. Though superficially similar, this is not the same as the Atkins diet. Possible long-term side effects of the diet include:

kidney stones
abnormal liver function
high cholesterol
weight gain
dehydration
bone thinning

The diet is typically supplemented with calcium, vitamin D, iron, and folic acid.

Among the possible reasons the diet was not widely adopted by doctors:

Lack of double blind studies. (see below)
Concerns about patient compliance with diet
Concerns about potential nutritional deficiency
It is possible that early anti-convulsants were statistically more effective than diets as treatment for new patients but that they worked on separate population groups.

The TV movie First Do No Harm increased awareness of the Ketogenic diet, though a curative link between fasting and epilepsy was even mentioned in the Bible.

Scientific Studies

A study conducted by Johns Hopkins reported that 50% of those patients starting the ketogenic diet reported a decrease in seizures of 50% or more, with 29% of patients reporting a 90% reduction in symptoms; these patients had previously tried an average of six anticonvulsant drugs. The success rate on patients who responded to anticonvulsants was not measured in that study (and appears to be lacking in other recent studies as well - there appears to be reluctance to try the diet on subjects except as a last resort). The success rate of the diet on those who are successfully treated with anti-convulsants may be higher, lower, or the same as those who do not respond. It may be that the diet and anti-convulsants are effective on different segments of the population.

The ketogenic diet has been reported to work in cases where multiple epilepsy drugs have failed. There may also be cases where the ketogenic diet has failed and epilepsy drugs succeeded. When one epilepsy drug fails, there is a high likelihood that other drugs will also fail. When the diet works, the response is often rapid and dramatic.

Double Blind Studies

Lack of double blind studies is an issue preventing wider acceptance by the medical profession. Reliance on proper studies rather than anecdotal evidence or flawed studies is important. Double blind studies help eliminate:

Placebo effect
Spontaneous remission
Researchers expectations may prejudice their observations
Researchers inadvertently prejudicing patients through body language, tone of voice, etc.

A double blind study of the Ketogenic Diet is underway.

Research and Variants

The diet usually referred to in the context of epilepsy treatment is the classic 4:1 fat to protein plus carbohydrate ratio John Hopkins Hospital protocol,^, but there is more than one type of ketogenic diet. There's also the Sanggye Paik Hospital protocol (also 4:1) developed by Drs Kim and Park, the medium chain triglyceride diet, the Atkins diet, and supplementation with polyunsaturated fats.

Kim Dong Wook and colleagues at the Inje University Sanggye Paik Hospital Epilepsy Center found that patients treated with the nonfasting, introduce high-fat foods to existing diet gradually protocol (August 1999-February 2001) achieved urinary ketosis just as fast, with just as much improvement in seizures, as patients using the initial fasting John Hopkins protocol (July 1995-July 1999), with 1/6 the dehydration and a shorter average hospital stay. A team led by Dr. Inna I. Vaisleib reported that same year that the 4:1 diet could also be done outpatient and with no caloric restrictions. According to Freeman et al, the ketogenic diet reduces atonic and myoclonic seizures by over 50% immediately.

Like any other therapeutic intervention, the ketogenic diet is not without adverse effects. In 2004, Drs Hoon Chul Kang, Da Eun Chung, Dong Wook Kim, and Heung Dong Kim reported that out of 129 patients who were on the diet at the Epilepsy Center at Inje University Sanggye Paik Hospital between July 1995 and October 2001, 46.5% experienced—in the 4-week trial period—dehydration, 38.8% experienced gastrointestinal symptoms (diarrhea (32.6%), nausea/vomiting (27.9%), and constipation (2.3%)), hypertriglyceridemia in 27.1%, hyperuricemia in 26.4%, hypercholesterolemia (14.7%), infections (pneumonia, cystitis, etc) in 9.3%, symptomatic hypoglycemia (7.0%), hypoproteinemia (5.4%), hypomagnesemia (4.7%), repetitive hyponatremia (4.7%), HDL hypocholesterolemia (3.9%), lipoid pneumonia due to aspiration (2.3%), hepatitis (2.3%), acute pancreatitis and persistent metabolic acidosis. After those first four weeks, the side effects, in descending order of prevalence, were gastrointestinal discomfort (27.9%), infectious disease (20.9%), hypertriglyceridemia (20.2%), hypercholesterolemia (19.4%), osteopenia (14.7%), hypomagnesemia (10.9%), hyperuricemia (7.8%), hepatitis (5.4%), lipoid pneumonia due to aspiration (4.7%), hypoproteinemia (3.9%), kidney stone(s) (3.1%), iron-defiency anemia (1.6%), secondary hypocarnitinemia (1.6%), HDL hypocholesterolemia (0.8%), symptomatic hypoglycemia (0.8%), hydronephrosis (0.8%), and cardiomyopathy (0.8%). The person who had cardiomyopathy died, along with three other people, one with lipoid pneumonia and the other two with sepsis.

Footnotes

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| url = http://pediatrics.aappublications.org/cgi/content/full/114/6/1627}}
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| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&list_uids=10482210&dopt=ExternalLink}}

External links

Epilepsy Action: The Ketogenic Diet
Johns Hopkins
Ketogenic Diet for people with ALS - A recent study (April 4th, 2006) by Mount Sinai School of Medicine shows KD diet may prevent progression of ALS
NICUS: Ketogenic Diet: Fact or Fiction?

Studies

Diets | Neurology