The Okinawa Centenarian Study is a research project that looks at people who live on an island called Okinawa in Japan and are over 100 years old (that's a really long time!). The researchers want to find out why so many people in Okinawa live to be so old and healthy (not sick or weak).
They ask the centenarians (people who are 100 years or older) questions about their diet, exercise, and habits, and compare them to the habits of younger people in Okinawa and other parts of Japan. They also look at their genes (which are like your body's instructions) to find out if they have any special ones that help them live longer.
They've discovered that the centenarians eat lots of vegetables, fruits, and tofu (a type of food made from soybeans) and not as much meat or dairy products. They also exercise regularly and have strong social support from their families and communities. Some of them also have a special gene called the FOXO3 gene, which might help them live longer.
The researchers hope that by studying these centenarians, they can find ways for other people to live longer and healthier lives.