As the average longevity of the population continues to climb, so does the number of people living beyond that average. It is no longer unusual to know friends and relatives who seem to have easily managed to get to 90 years old and beyond. We are still wowed, however by people who get to 100, known as centenarians, and people who get to 110 or more, now that is really something.

Those few who make it to 110 and more are known as supercentenarians. This achievement is still somewhat rare, but it is much more common than it was just half a century ago. Before 1960 there were only three reported cased of people living beyond 110 in the entire world. Today, in 2017, there are 42 supercentenarians still alive, 41 women and one man. There is an estimate that seven out of every 1,000 people born at the turn of the last century lived to be 100 or more, and only one in 100,000 live to be over 110.

Scientists study these extraordinarily old people to try to find out what about them allowed them to live so long. Perhaps knowing their secrets can help the rest of us prolong our own lives, or prolong good health while aging. Preliminary studies have shown that not only do supercentenarians live longer, but they also age more slowly. Illnesses that are age-related, like dementia, cancer and stroke, affect them later in life.

“About 25 percent of how long a given person lives is due to genetic factors, and the rest is really luck and lifestyle,” said Stuart Kim.

Kim is a researcher studying aging, previously at Stanford University. He is particularly interested in that 25 percent, the genetic make-up of those that live much longer than average.

“One way that a person could live to 100 is just luck — they didn’t have cancer, heart attack, or stroke. But if I look at that person, he’s going to look 100 years old,” said Kim. “The other potential is that a person might be aging slower, and after 100 years, this person only looks 70 years old, which is also the reason why he hasn’t had cancer, stroke, etc.”

But what about the other 75 percent of staying healthy longer, the influences we control?

“Other than some of the obvious characteristics, such as good physical health and high cognitive functioning, we also should consider social aspects such as good social relationships and social engagement, the personality of older adults, and the rich experiences that make up an important part of an individual,” said Peter Martin, gerontologist at Iowa State University.