In 1993, Jim Abrahams was desperately trying to find a treatment for his son Charlie, who suffered from severe epilepsy that did not respond well to drugs. The father stumbled across the ketogenic diet, which resulted in seizure freedom for his son. However, Jim was shocked that multiple specialists did not tell him about the ketogenic diet. Some doctors even discouraged him from trying it for his son. Outraged at the situation, Jim used his talents and connections as a Hollywood producer/writer/director to make the TV movie First Do No Harm starring Meryl Streep. He was also profiled in a 1994 Dateline segment on the ketogenic diet. You can view the Dateline segment on The Charlie Foundation’s Youtube channel.
Jim Abrahams switched career paths to start The Charlie Foundation, a non-profit dedicated to raising awareness about the ketogenic diet and helping patients implement it. The Charlie Foundation and Jim Abrahams’ work was instrumental in the explosion of papers on the ketogenic diet following its creation in 1994.
So why was the ketogenic diet unpopular prior to 1994? In the 1994 Dateline segment (10:47 into the video), Dr. Donald Shields explains that the ketogenic diet lost popularity since the 1920s because there wasn’t a pharmaceutical company selling it to doctors. The history of the ketogenic diet shows that medical treatment isn’t always driven by science.
A 2014 review of the literature summarizes the pros and cons of the diet well:
In summary, KD [ketogenic diet] and MAD [modified Atkins diet] treatment show modest efficacy, although in some patients the effect is remarkable. The diets are well tolerated, but often discontinued because of their restrictiveness. In patients willing to try dietary treatment, the effect is seen quickly, giving patients the option whether to continue the treatment.
Some points of interest about the diet:
It works in adults. The 2014 review mentioned earlier summarizes the research on adults. However, it is likely that adherence is lower in adults than children and infants.
Is it difficult to adhere to? This varies from person to person. Some people love the ketogenic diet because they experience seizure freedom without the side effects of drugs, are no longer obese, feel improved mental clarity (no “brain fog”), and/or see other unexpected health benefits. Others find the initial adaptation period to be brutal, dislike how socially restrictive the diet is, and/or find the diet difficult to stick to. Perhaps the best way to find out is to simply try the diet.
The medical version of the ketogenic diet differs from the popular version that people use to lose weight. Some notable differences include:
It is unclear if these differences lead to a medical benefit (or harm). Similar diets used to treat epilepsy do away with many of these restrictions to make the diet easier to follow. The second most studied diet, the Modified Atkins Diet, is shown in some studies to have similar success rates and is shown in other studies to have somewhat lower success rates. The Charlie Foundation website has a good summary of the differences between the various diets used to treat epilepsy.
There are side effects. While one can argue that the ketogenic diet has fewer side effects than many AEDs, it does sometimes lead to side effects. One serious side effect is kidney stones (renal calculi) in 3-7% of children on the diet. This number could be lower via supplementation with citrate / Polycitra K where risk of kidney stones is high. Growth in children may be lower, although there is conflicting data.
The diet can lead to cholesterol levels that are considered unhealthy, although this is controversial because the scientific evidence suggests that cholesterol levels are extremely unreliable in predicting death from cardiovascular disease. For example, the Minnesota Coronary Experiment found that lowering of cholesterol was associated with higher rather than lower mortality.
For a discussion of other side effects, see:
 Early‐ and Late‐onset Complications of the Ketogenic Diet for Intractable Epilepsy – This Korean paper reports side effects in children.
 Optimal clinical management of children receiving the ketogenic diet: Recommendations of the International Ketogenic Diet Study Group – Skip ahead to the section on Adverse effects of the KD. It discusses the conflicting data on the effect of the KD on growth in children.
The diet is the treatment of choice for specific conditions. Table 1 of this 2009 review paper lists epilepsy syndromes and other conditions where it is particularly beneficial:
For more information on how to implement a ketogenic diet (e.g. to find a dietitian who understands the diet), The Charlie Foundation’s website has a wealth of information.
Egger at al. used an elimination diet on patients and instructed them to slowly re-introduce foods to identify their specific food intolerances. For children with epilepsy as well as migraines or hyperkinetic behavior (ADHD), 25 out of 45 (56%) became seizure free while another 11 out of the 45 (24%) had fewer seizures. Their results and diets on the diet were published in the following paper:
Egger, J., Carter, C. M., Soothill, J. F., & Wilson, J. (1989). Oligoantigenic diet treatment of children with epilepsy and migraine. The Journal of Pediatrics, 114(1), 51–58. doi:10.1016/s0022-3476(89)80600-6
Unfortunately, Egger’s work (while recognized among migraine researchers and cited frequently by them) has been more or less ignored by epilepsy researchers.
Some additional notes:
The paleolithic ketogenic (PKD) diet is even more of a pariah in the research community than the oligoantigenic diet as it is basically an all-meat / carnivore diet. The PKD diet consists of meat, animal fat, fish, offal (e.g. liver and brain), and eggs. While the diet may seem extreme by Western standards, the Inuit (Eskimo) have consumed all-meat diets for generations and enjoyed excellent health before they began to adopt Western ways of eating. Arctic explorers of non-Inuit descent have also eaten all-meat diets without health problems (see Vilhjalmur Stefansson’s series of articles in Harpers magazine).
The diet shuns foods with a poor track record (or no track record) when it comes to human health. For example, it is known that gluten is a rare cause of epilepsy as well as a wide range of other conditions. One difference between the paleo ketogenic diet and the classical ketogenic diet is that the paleo ketogenic diet explicitly excludes gluten.
Regardless of the diet’s pariah status, it may be of interest in treating epilepsy. The following case studies have been published:
The PKD diet was developed by Zsofia Clemens and Csaba Toth, the brains behind a clinic in Hungary called Paleomedicina.
Potential advantages of the diet are:
See this primer on all-meat diets for more details on the PKD diet.