From Netflix documentaries to special diets, there has been more and more talk of so-called ‘Blue Zones’, areas of the world where there is a high concentration of centenarians. But, is it all bogus? And how can we trust the ages of the super old?

Joining Seán to discuss is Saul Newman, from the Centre for Longitudinal Studies at University College London, who has just won an Ig Nobel Award for his research in this area…