Is 100 the new 78? A growing number of voices are insisting that you need to be planning a life that will last well past 90. Possibly past 100. And definitely long past 78 which, at birth, is your longevity in the U.S.

Living longer impacts just about everything from how much savings you need to how long you work. Suddenly, living longer than the retirement savings last looks like a very real worry. "Longevity is a big factor in financial planning for retirement," said Ted Goldman, the senior pension fellow of the American Academy of Actuaries and an expert on longevity risk.

Ohio attorney and retirement planner Kevin Fields insisted that worrying about going broke in old age is not irrational. "When you couple increased longevity with the substantial decrease in traditional pension plans being offered by employers, the likelihood that individuals will outlive their retirement savings has increased significantly," he said.

As for how long we are likely to live, Dr. Tom Perls, who has run the New England Centenarian Study at Boston University Medical Center for 25 years, said that in just that time span "centenarians" - people 100 and older - "have doubled. It is 1 per 5,000 people. Before it was 1 per 10,000."

Properly concerned now? "It's a wake-up call to realize you may live to be older than 90," said Perls. He added: "People's perception of what 65 is has dramatically changed."

That is fact. Before, 65 was a marker signaling the approach of end of life. Of course, many had already died before then. But nowadays cheap, effective medicines are helping control cardiovascular diseases, cancer detection and treatment have gotten better, and many of us have eliminated the bad behaviors - such as smoking, eating too much, and not exercising - that hasten earlier deaths. The upshot is suddenly lives are longer.

If you liked this article you might like

There Is a Perilous Shortage of Elder Caregivers

The Coming Culture Wars in the Trump Era: Frugality vs. Consumption

Can You Retire Abroad on Social Security Alone?

Are You Emotionally Ready to Retire?