"The calendar may say they're 80, but their body says they're 60," says Bradley Willcox, a scientist researching the extraordinary phenomenon. The research has shown hormonal differences between Okinawans and B _______ but their longevity has been linked to diet. They eat more tofu and soya than any other people in the world and also enjoy a range of different fruit and vegetables, all rich in anti-oxidants. But the most significant thing isn't what they eat but how much. The Okinawans C _______ known as 'hara hachi bu', which translates as 'eat until you are only 80% full'.