Peter Martin (far right), director of Iowa State's gerontology program, has been conducting research on centenarians and the oldest of old for more than 20 years. Credit: Bob Elbert, ISU News Service

(Medical Xpress) -- Spanish explorer Ponce de León searched for the "Fountain of Youth" in hopes of finding eternal life. And while Peter Martin, director of Iowa State University's gerontology program, hasn't found the mythical fountain, he and his research team have determined behavioral factors that may increase longevity.

Martin (right) is the lead author of a new article summarizing the keys to long life. The article appeared online last week in the Journal of Aging Research as the introduction to a special issue on the behavioral factors of longevity, which Martin edited.

He also had three of his related studies published in the special issue and says all the research found in that issue supports the "Georgia adaptation model" that he and fellow researcher -- Leonard Poon from the University of Georgia -- had constructed some time ago.

"Long before we did this [journal special issue], our team came up with a model of longevity and it's still one of the only models out there that says, 'These are the factors that contribute to longevity and well-being in late life,'" said Martin, an ISU professor of human development and family studies (HDFS). He has conducted research on centenarians and the oldest of old for more than 20 years.

Six behavioral factors of longevity

Martin reports both the model and new research identify these six behavioral factors of longevity:

1. Environmental support

"In other words, social supports," Martin said. "You cannot get there [long life] by yourself. You've got to have family, or community, or care facilities. And you also need economic support -- the financial resources to last into very late life."

2. Individual characteristics

"This has to do with such obvious things as gender, where women are more likely to make it to a very old age than men," Martin said. "Certainly there are also ethnic group differences or disadvantages. We know that life expectancy is higher for whites and lower for African-Americans. And we also consider personality, so a certain configuration of personality characteristics gives you a much better opportunity for long life."

3. Behavioral skills

"These are things that you do every day. And that has to do with good coping, being an active person, good cognitive functioning, etc. All of these are very important to promoting long life," he said.

4. Good nutrition and health behaviors

"There are articles in this special issue that indicate what we eat and how we stay fit are all important," Martin said.

5. Staying healthy

"These are the things that you can do to stay in good physical health," Martin said. "Of course some of it is biological, but much of it is our responsibility to stay healthy."

6. Good mental health

"Depressed people are not real likely to make it to very old age," he said. "We see that [very old age] in optimistic people."

The academic literature has mapped out a path to long life, according to Martin.

"As I've often said, longevity is much less of a secret than we think it is," he said. "It's often the things that research has talked about. It's just that people would like to have the one thing that explains longevity. And with these various clusters of variables, we've found that it's not one thing -- and what works for you may not work for me."

Three other studies

Martin authored three studies in the Journal of Aging Research special issue that contribute to the literature on the behavioral keys to long life. One study of 306 octogenarians and centenarians from the Georgia Centenarian Study -- co-authored by Jennifer Margrett, an ISU assistant professor of HDFS -- found that a subject's subjective health assessment was more important to their emotional well-being than the medical facts about their health.

"Your own assessment [of how you feel] in many ways trumps the doctor's assessment [or your health]," Martin said. "Maybe that isn't such a surprise. When you go to the doctor, what's the first thing he's going to ask you? 'How do you feel?' They start out with subjective assessment, and there's a reason why they ask that."

And in a study of 137 centenarians and later 68 survivors from the Georgia Centenarian Study, Martin and fellow researchers found that cognitive decline compromises centenarians' satisfaction with life. However, the extent of that impact is also influenced by whether they're emotionally happy.

"So our challenge to those working with old people is to think long and hard about how we can create positive experiences in the daily lives of very, very old people," Martin said. "This study found that particularly as the memory declines, the positive emotions decline too. So it's even more critical to create positive experiences as there are some cognitive challenges."

Martin and Margrett also studied how living in private homes, assisted living facilities and nursing homes affects centenarians' support-efficacy model, and therefore their physical and mental health.

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