In many communities, it often makes the front page of the local newspaper: that is, a resident celebrating a 100th (or even older) birthday. For example, there was recently much hoopla in the town of Willits, CA when 116-year-old Edith Ceccarelli (the oldest person in the US and second oldest person in the world) celebrated her birthday. And it’s such a milestone that you can even request a birthday greeting from the President of the United States on the occasion of your 100th birthday. No doubt, it’s a landmark event when someone reaches the age of 100. But it’s not quite as rare as it used to be, and scientists are hot on the trail of determining what allows a person to become a centenarian or even a supercentenarian (ages 110 and above) and how average individuals can strive for that goal. Of course, whether you want to strive to reach age 100 or beyond has much to do with the state of your health. If your health span starts to decline in your 60s (apparently, “the average American can expect to celebrate only a single birthday in good health after the traditional retirement age of 65”) living to 100 may not be so desirable. But studying those who do live that long, especially those who reach that age in relatively good health, may be valuable for understanding how to increase the health spans of those who are getting older, even if they will never see the light of day at age 100. So it’s useful to study why and in what condition people reach their centennial birthday, along with understanding the wisdom they’ve gained along the way.

First, some statistics. According to the Pew Research Center, currently, just over .03% of the US population (around 101,000 people) are centenarians, with the majority of them being women (78%). That number is nearly triple the number of centenarians who existed in 1990. By 2054, it’s estimated that .1% of our population, or approximately 422,000 will be centenarians. Worldwide, it’s estimated that there are currently 720,000 centenarians, with the US population the largest, second only to Japan. By 2054, the worldwide centenarian population is expected to reach nearly 4 million people. What’s causing this burgeoning population growth? There is definitely a genetic component to this and scientists are also beginning to discern blood biomarkers that differentiate centenarians from those whose lives are shorter. In a new study published in GeroScience, researchers were able to report that those who lived to 100 or older had common biomarkers different than those who died at an earlier age. The biomarkers are related to inflammation, metabolism, liver and kidney function, along with glucose and cholesterol levels. While scientists cannot make a definitive link between these biomarkers and exceptionally long lives, there does seem to be some association that both genes and lifestyle play a role in longevity (along with good luck). For more on this study, read here. There is also extensive research going on in Japan, home to the largest number of centenarians, regarding what allows these very old adults to live as long as they do and whether those insights can help extend the health span of all older adults.

Another recent study in the Journal of Happiness Studies, also suggests that there are personality traits common to centenarians. In this Spanish study, which involved interviews of 19 individuals (mostly women) between the ages of 100-107, traits such as commitment, social engagement, positivity, and resilience were common to all. What also appears to be common among centenarians is what’s called “compressed morbidity:” that is, their poor health and decline are compressed into a shorter time period towards the end of their lives and in fact, the overwhelming majority of them function independently until about age 93. Almost none of them have ever smoked and they can be generally grouped into 3 categories: “survivors” who dealt with age-related disease before the age of 80, “delayers” who were diagnosed after age 80 but have proved resilient and “escapers,” who have no major chronic disease as they approach 100. Furthermore, despite living such lengthy lives, centenarians tend to have fewer healthcare costs than those who die earlier, as they spend less time in ICUs and using “heroic” measures and more time in their final days utilizing hospice.

And what wisdom do those who have reached these milestone birthdays have for us? Recently, The Washington Post published an article filled with wisdom gleaned from 14 centenarians around the world. In many respects, their advice and behaviors mirrored the personality traits referenced above: They were resilient in the face of adversity, committed to a professional or personal passion (one 107-year-old woman continues her enthusiasm for hair cutting), remained positive about the future, and believed in hard work. But there were also recommendations about kindness, humility, discipline, exercise, and education. For more on their sage advice, lend an ear and click here.