They are working on a blood test which, should we really want to find out, would reveal who will be a centenarian.

Researchers identified 281 genetic markers associated with longevity after examining 800 pensioners with an average age of 104 along with a control group of people of all ages.

Many in the study had managed to reach their advanced age despite unhealthy lifestyles.

This led U.S. scientists at Boston School of Medicine to conclude that their genes appeared to ‘trump’ that behaviour.