The ketogenic diet (KD), a high-fat, low carbohydrate regimen, is being increasingly used to treat brain disorders, including epilepsy. The limited intake of carbohydrates in the diet forces the body to use fats as its primary fuel source, triggering a state known as ketosis. Ketosis has been shown to reduce seizure frequency, although the exact reasons are not well understood. Since nutrition is linked to overall health, the KD can affect other body systems, including the immune system. Leukocytes, or white blood cells, are specialized immune cells that help the body to fight infections. A decrease in the number of a particular type of white blood cells, known as neutrophils, is called neutropenia, and this condition weakens the immune system, making it more likely that an infection will occur. To examine the link between the KD and neutropenia, Dr. Elizabeth Donner and her research team reviewed the medical charts of children with epilepsy who started the KD at SickKids Hospital between the years 2000-2018.
Of 102 children studied, 13 already had neutropenia when starting the diet, possibly related to the other epilepsy treatments they were prescribed or other medical conditions. Of the remaining 89 children, 27 developed neutropenia during KD therapy, and the longer they were on the diet, the more likely it was to develop.
Like all children, those on the KD frequently have the common infections of childhood such as colds and stomach flu. The research team also found that 65% of the children developed an infection that required medical treatment while on the KD. However, the researchers did not find a link between the timing of the infection and the development of neutropenia. Most infections occurred while patients had normal levels of neutrophils, which suggests that neutropenia did not lead to infections. In addition, most occurrences of neutropenia were temporary and cell counts returned to normal levels by the next appointment.
In conclusion, although the researchers found a link between the development of neutropenia and the KD, the decreases in neutrophil counts were generally mild and did not lead to infections. The authors conclude that concern regarding neutropenia should not discourage the use of the KD in children.