Scans of the rodents’ liver cells found insulin, the hormone released by the pancreas when they ate food high in sugar and starch, had an effect on the cells’ circadian rhythms.

Dr Makoto Akashi, one of the lead researchers on the project, said: ‘In short, insulin may help the stomach clock synchronize with mealtime.

‘For example, for jet lag, dinner should be enriched with ingredients promoting insulin secretion, which might lead to a phase advance of the circadian clock, whereas breakfast would be the opposite.’

There would be side effects to using insulin to treat insomniacs, Dr Akashi warned.