Approximately 1% of children in the United States have epilepsy, a condition characterized by repeated seizures. Although in most cases seizures can be controlled with medication, some children are unresponsive to medical intervention of this sort. With few other treatment options available, some neurologists are turning to an old medical practice—dietary manipulation. While more commonly associated with a popular approach to weight loss, therapeutic ketogenic diets (those stimulating ketone production in the body) have also long been recognized as a method for controlling seizures in children with difficult-to-control epilepsy . First developed in the early 1900s, ketogenic diets were the standard treatment modality until antiseizure medications became widely available. Ketogenic diets are intended to mimic starvation through dietary manipulation so that brain cells rely heavily on ketones instead of other energy-yielding substrates, such as glucose, for a source of energy. To deplete...