Daily rhythms are evident across our physiology, ranging from overt behavioural patterns like sleep to intricate molecular rhythms in epigenetic coding. Driving these rhythms at an anatomical and cellular level are circadian clock networks comprising core clock genes and an ever-expanding list of clock-controlled genes. Research over the past decade has revealed an intimate relationship between the clockwork and metabolic processes. In line with this, feeding behaviour in many species exhibits a strong circadian rhythm and, when restricted, food becomes the most potent entraining stimulus for clocks of the body. Critically, there are several indications that disturbance of our daily rhythms contributes to the development of obesity and diabetes. Given our 24-h society, it is important that we understand how the circadian clock influences what and when we eat.