Circadian rhythms, diet, and neuronal excitability.

Many aspects of normal biological function are governed by circadian rhythms, including metabolism, ingestive behaviors, and sleep-wake cycles. Certain pathological processes as well are also affected by the circadian rhythms. For example, it is well known that seizure occurrence can be influenced by the sleep-wake cycle. The ketogenic diet (KD) is a high-fat, low-carbohydrate diet with proven efficacy in the treatment of intractable epilepsies. While the mechanisms underlying the clinical effects of the KD remain unclear, there are emerging links between circadian rhythms and KD action. Such factors should be considered when planning and administering the KD to patients.