What factors increase our chances of becoming a centenarian? While science remains cautious about the secrets of longevity, there are several hypotheses (many of them supported by studies) to explain why some of us reach old age and others do not. In France, the number of centenarians has multiplied by 100 between 1950 and 2015. How could you achieve this? We had fun drawing up a list of commandments to respect to put the odds on your side!