"Everybody says your mind is the most important thing about your body. Your mind and your body. You keep both busy, and by God you'll be here a long time," said Walter Breuning, before his death this month. And he should have known: at the age of 114, Breuning was the world's oldest man.

Born in Minnesota in the US in 1896 – the year Henry Ford built his first car, the landmark Plessy v Fergusson case declared racial segregation constitutional in the US – Breuning lived through two world wars, the birth of television, the advent of the internet and the death of his wife more than 50 years ago.

The secret to a long life, Breuning said, was eating just two meals a day, working hard (he retired in 1963 at the age of 67) and always being open to change. What would you add to this list? Do you have any other tips for a long and fulfilling life?