Johns Hopkins has been doing research and clinical trials on ketogenic diets for seizure disorders in children for years. The diet they use is much more carb-restricted than we find in PP, and probably higher in fat content. The article in Diabetes in Control describes it this way:
The ketogenic diet, consisting of high-fat foods and very few carbohydrates, is believed to trigger biochemical changes that eliminate seizure-causing short circuits in the brain’s signaling system. Used as first-line therapy for infantile spasms and in children whose seizures cannot be controlled with drugs, the diet is highly effective but complicated and sometimes difficult to maintain. It can temporarily raise cholesterol, impair growth and, in rare cases, lead to kidney stones, among other side effects.
The Hopkins Children’s Hospital used the diet for 16 months to 8 years to reduce or eliminate the seizures. The study being referenced is a follow-up to see if any lasting health problems from the diet are revealed.
There don’t seem to be any long-term effects:
Only two of the 101 patients reported kidney stones after stopping the diet, the same rate found in the general population not treated with the ketogenic diet, the researchers say.
None of the 25 patients who had liver and kidney function tests had abnormal results. Among the 26 patients who had their cholesterol tested, the average level was 157 milligrams per deciliter of blood (less than 200 is considered normal), with three of the 26 having abnormal levels. Most patients’ cholesterol levels go up while on the diet, but are believed to return to normal thereafter. The Hopkins study now confirms that this is the case.
In 2008, Johns Hopkins Children’s Hospital described the results on cholesterol this way:
While most children developed high cholesterol after starting the diet, in half of them, cholesterol gradually improved returning to normal or near-normal levels, with or without modifications to their diet to reduce fat intake.
Interestingly, efforts to reduce saturated fat saw no greater decrease in cholesterol levels. In other words, doing nothing and reducing saturated fat had the same effect over time. That might be good news for low carbers that are worried about an increase in cholesterol in the early years of the new way of eating.
Since 2005, Hopkins has noted that a modified Atkins low carb diet plan has nearly the same benefits as their more restrictive ketogenic diet for children with seizure disorders. In effect, any diet that puts the patient into ketosis restricts the seizure activity.