SAN FRANCISCO, Calif. - Molly Greenberg loved the horse-and-buggy rigs as a child in New York, even as the new-fangled Model T car was becoming popular. Women didn't have the right to vote when she was born in 1912, and their life expectancy was 56 years.
A century later, she's had the last laugh on a lot of things.
Greenberg has voted in 20 presidential elections, she's nearly doubled that life expectancy, and her mind is so sharp she can debate the benefits of computers.
It used to be that people who made it to 100 years old were fuzzy-minded at best, and they numbered mighty few at that. Not so much anymore.
"Oh, my, the changes I've seen," Greenberg said one recent afternoon at her Oakland, Calif., senior-complex apartment. "I've actually liked a lot of them. Man going to the moon was one, I'll say that.
"Cars are nice, too, even though I haven't been able to drive for about a decade," she said with a chuckle, "and it certainly is easier to get my favorite strawberry ice cream these days than it was when I was a little girl."
There are more centenarians in America than ever before, according to new figures from the 2010 U.S. Census.
The increase is due to more than simply population growth. Fueled by advances in medical care and health practices, the number of centenarians in the United States grew by 66 percent between 1980 and 2010 to 53,364, while the total population increased 36 percent.
Only about 35 percent of people over 100 nationwide live in a nursing home, requiring around-the-clock care -- down significantly from 48 percent as recently as 1990. That means most of the rest are living with family or independently, and experts say that number will grow in coming years.
"The baby boom generation has been having its surge into the older ages for a few years now," said Hans Johnson, demographer with the Public Policy Institute of California. "And since the oldest baby boomers were born in 1946, the oldest are still only 67. So there is a lot more growth to come."
The trouble for many people as they become very elderly is that most assisted-living complexes cost from $4,000 to $10,000 a month, and around-the-clock nursing homes run more than $5,000 a month.
If a person retires at 65 and makes it to the life expectancy for current U.S. residents of 81 years for women and 76 for men, it puts a strain on the nest egg. Social Security checks topping out at $2,500 a month help, but can't carry the load.
"Keeping Medicare and Social Security solvent are going to be huge issues," Johnson said. "A lot of people have value in their houses, and will use that, but they will go through that money very quickly."
Greenberg is typical of American centenarians in at least one respect -- she's a woman. Just 17 percent of people 100 and older are men, which isn't surprising considering societal habits, experts say.
"For men 85 years and older, heart attacks from stress, smoking, war, things like that are more likely causes of death than for women," said Dr. Rebecca Conant, a geriatrician and associate professor at University of California, San Francisco. "And so by the time they get to 100, a lot of men have been pruned out of that age group."
Greenberg's nephew Stewart Jacobson, 64, an entertainment producer and author in Florida, said he thinks his aunt's longevity secret is maintaining a happy attitude. It also helps that she's able to afford her unit -- her late husband, Ed, was a successful film promoter in Hollywood and left her well-cared for when he died at age 86 in 1997. Her family, which includes a son and daughter in their 60s, also help out.
"Her spirit of life is always wonderful," Jacobson said.
Cheerfulness, however, takes one only so far. Greenberg notes that her mother made it to 90, her father 86, and seven brothers and sisters all passed away in their 90s. Her remaining siblings are 90 and 92.
Other than be blessed with good genes, her advice: "Don't smoke, don't overeat, and don't drink too much."
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