In a trend that will come as no surprise to those who are searching for the secret to longevity, more Americans are reaching the age of 100 these days, reports Sabrina Tavernise for The New York Times. These long-lived centenarians are also living even longer, with a death rate that has actually fallen in recent years.

In 2014, there were 72,197 Americans aged 100 or older, according to a report from the Centers for Disease Control and Prevention. That number is up 44 percent from 2000, when there were only 50,281 centenarians.

"There is certainly a wow factor here, that there are this many people in the United States over 100 years old," William H. Frey, the senior demographer at the Brookings Institution, tells The New York Times. "Not so long ago in our society, this was somewhat rare." Improvements in vaccines, antibiotics, hygiene and sanitation are all likely to blame for the increased survival to advanced ages.

"People are more aware of their health, of the importance of staying active and eating healthy food," the CDC report's author, Jiaquan Xu, tells David Beasley for Reuters. The improvements to overall health can be seen in the shifting causes of death among the centenarian set.

While heart disease, stroke and cancer—leading causes of death for all Americans— still rank in the top causes for death among centenarians, Alzheimer's disease has crept up in the rankings. Deaths from this disease increased 119 percent since 2000. Xu attributes the Alzheimer's increase to a greater awareness of the disease and therefore more diagnoses, Reuters reports.​

"People who are physically fit enough to survive over 100 years ultimately succumb to diseases afflicting the mind and cognitive dysfunction," Holly Prigerson, a professor in geriatrics at Weill Cornell Medical College, tells Rachael Rettner at Livescience. "In other words, it appears that their minds give out before their bodies do," says Prigerson, who was not involved in the CDC work.

Inevitably, a person who lives past 100 gets asked what their secret is.

The world's current oldest resident, Susannah Mushatt Jones, chalks her longevity up to not drinking, smoking or partying, reports NBC. Now 116, this Brooklyn resident sleeps a lot but still enjoys four delicious strips of bacon each morning, writes Christopher Bonanos for New York Magazine.

Malvina Hunt, who lives in the Finger Lakes region of central New York, credits her health to vigorous exercise. "Whatever muscle seems weak, I give it a little bit of touch-up," Hunt tells The New York Times. Leg lifts and arm raises every morning, supplemented with bowling ("That gives me a good workout"). Her job as a greeter at a local winery also gives her the opportunity to help build the cartons used to ship wine. During the summer she gardens and mows the lawn.

She says: "My motto was always, 'If I could do it today, I’ll be able to do it tomorrow.'"