A growing number of Americans are now surviving past the 100-year mark, and many are doing quite well, thank you. 

A positive outlook and a robust spirituality may be crucial to a healthy, happy life for most centenarians, a new survey finds. 

The survey, 100 at 100, was conducted by Evercare, a health insurance plan that specializes in older people. 

"Health is more than the medical aspects," said Dr. John Mach, Evercare's CEO. "It's important to know the social and psychological makeup of people who have remarkable longevity," he said. 

Americans over 85 are the fastest-growing segment of the population, Mach said. "It is important to understand what is important to these people, so we can care for them," he said. 

In the survey, telephone interviews were conducted with 100 adults (66 women, 34 men) who were 99 years old or older, two-thirds of them between 100 and 104. 

One expert said the poll may not represent most of the over-100 crowd, however. 

"This is a select group of centenarians," said Dr. Margaret Drickamer, director of Integrated Model of Aging and Geriatric Education at Yale University School of Medicine. "They were able and willing to do a telephone interview. There is no indication as to those physically or cognitively unable to do the interview." 

For example, New York City socialite heiress Brooke Astor, who is 104, has recently disappeared from public view and is now the center of controversy surrounding her care. Drickamer said that for many centenarians, this type of dependency, illness and frailty is more the norm. 

"There is a difference between those who live to be 100 and those who survive to be 100," she added. 

But among the 100 people surveyed in the Evercare poll, 71 percent rated their current state of health as good or excellent, Mach said. 

Few interviewees had real regrets about how they had lived. According to the poll, 61 percent said there was nothing they would have done more of in their lives, and 78 percent said there was nothing they would have done less of in the past. Thirteen percent said they wished they had traveled more, 9 percent wished they had worked less, and 6 percent wished they had spent more time with their families. 

Twenty-three percent credited their long life to their faith and spiritual care, while only 3 percent said it was due to genes or medical care. Other contributing factors cited were working hard, a healthy diet, living a good, clean life, not smoking and care and love from their family. 

Among those surveyed, 30 percent said that raising a family was their most satisfying achievement in life, followed by careers (20 percent), having lived a long life, marriage and education (6 percent each). 

Thirty-nine percent said that either their 20s or 30s were the best time of their lives, although 11 percent said they were happiest right now. No one said their 70s were their best years, only 1 percent said it was their 80s, and 2 percent said it was their 90s, the researchers found. 

Although many had thought about their own death, only 4 percent said they actually feared it. Faith and spirituality played a central role in how many were preparing for the future, with almost 70 percent believing in a life after death. 
"Despite the fact that these people have lived a long time, they are prepared for the future," Mach said. 

Another expert believes the survey results paint a positive picture of aging, one that many people may be able to achieve. 

"This is a very nice model for healthy aging," said Dr. Michael Steinman, from the San Francisco VA Medical Center and an assistant professor of medicine at the University of California, San Francisco. 

"What we aim for is not to view aging as a disease, but as a normal part of the lifespan, and we want to find ways for people to age in a healthy way - so that their later years are times of happiness both for things they are experiencing in the future as well as reflecting on the past, rather than being burdened by the afflictions of old age," Steinman said.