Researchers looking at mice on different diets found those who were fed fewer calories in a single daily feeding lived longer than mice eating the same number of calories distributed throughout the day.

"Instead, calorie-restricted diets ensure that mice are fasted for much of the day – and that imposed fasting-period (when we eat) is critical for the benefits of calorie restriction to life and health.".

Mice with constant access to a low-calorie diet, on the other hand, lived lightly shorter lives than the control group, even though they consumed fewer calories.

Though their longevity was not measured, the mice in the last group – which fasted without reducing calorie intake – showed just as many health benefits as the group that ate fewer calories and fasted.

Mice on a low-calorie diet who ate throughout the day meanwhile did not show benefits such as better blood sugar control, improved strength in old age, and longer life.