June 20, 2005

The Journal Report: Personal Health
The Secrets of Successful Aging
What Science Tells Us About Growing Older -- And Staying Healthy
By TARA PARKER-POPE
Staff Reporter of THE WALL STREET JOURNAL


Today, the average person in the U.S. lives for nearly 78 years.
But what about those people who beat the average? Why do some men
and women defy the chronological odds to live longer and in good
health?

Increasingly, the scientific community is shifting its focus to
this elite group, these "successful agers" who seem to be doing
a better job of getting old than the rest of us.

And what they're finding isn't what you'd expect.

Some of the reasons people age well are obvious. For years we've
been told that the best way to stay healthy is to eat the right
foods, maintain a healthy weight, exercise -- and hope you have
good genes. While all of that is true, a voluminous body of aging
research shows that some of the most significant enemies of old
age are far more insidious than a penchant for fried food or a
couch-potato lifestyle. Instead, how well we age may be
intrinsically tied to our most basic personality traits, the
social relationships we have formed and -- perhaps most important
-- our ability to cope with stress.

"We now know that aging is about a body that doesn't deal well
with stress anymore," says Robert Sapolsky, a Stanford University
neuroendocrinologist and a leading stress researcher.

Living to the Max

Scientists estimate that the maximum potential life span of the
human body is about 120 years, give or take. They came to this
conclusion after observing the oldest ages achieved by a variety
of organisms, noting that aging, no matter what the species,
seemed to follow a consistent mathematical formula. The maximum
age achieved by any species appears to equal about six times the
number of years from birth to biological maturity. So humans,
who take about 20 years to reach maturity, have the potential to
live six times as long as that -- or about 120 years. Notably,
the oldest well-documented human age is 122.


Genetics likely plays some part in the ability to reach an extreme
old age, and scientists are on a heated quest to identify the
so-called longevity genes. But genetics can only take you so far.
Studies of Swedish twins who were raised apart showed that only
about 30% of aging can be explained by genes. In other words,
successful agers aren't still around simply by luck of the
genetic draw. They have far more control over the aging process
than once thought.

"One of the myths of aging is to choose your parents wisely," says
John W. Rowe, who, before becoming chairman of Aetna Inc., served
as director of the MacArthur Foundation Research on Successful
Aging, one of the largest aging studies in the country. "People
feel there is a genetic program they are playing out. But since
only about one-third of aging is heritable, the rest is acquired
-- that means you are responsible for your own old age."

So, how do you age successfully? Aging researchers are beginning
to get some answers. Numerous studies of rats, monkeys, nuns,
British government workers and centenarians have unlocked many of
the secrets of successful aging.

____________________________________________________________________
Aging: By the Numbers
11: The number of additional years a 75 year-old man can expect
    to live

13: The number of additional years a 75-year-old woman can expect
    to live

17: The number of additional years a 65-year-old man can expect
    to live

30: The percentage of 80- to 102-year- old women still having sex

35: The age at which you begin losing more bone than you make

40: The waistline measurement, in inches, at which risk for heart
    attack increases dramatically

45: The age at which disease becomes a bigger mortality threat
    than accidents

63: The percentage of 80- to 102-year- old men still having sex

65: The number of validated "super centenarians" in the world,
    still alive at 110 or beyond

70: The new 65, based on the health of 65-year-olds in 1973

74: Average life expectancy for a boy born in 2001

80: Average life expectancy for a girl born in 2001

85-94: The fastest growing age group in America

120: The estimated potential life span of humans, if nothing
     goes wrong

122: The oldest fully authenticated age to which any human
     has lived

Sources: Living Better, Living Longer; Harvard Health Publications;
National Vital Statistics Reports, Centers for Disease Control

____________________________________________________________________

Many of the answers were expected. People age better if they don't
smoke, don't abuse alcohol, maintain a healthy weight and get
regular exercise.

But one of the biggest culprits in unhealthy aging also gets the
least respect from both the medical community and individuals:
stress. Increasingly, researchers are viewing stress -- how much
stress we face in a lifetime, and how well we cope with it -- as
one of the most significant factors for predicting how well we age.

It may be hard to believe that stress, which most people view as
an emotional state, can wreak such havoc on our physical well
being. But aging studies consistently show that the healthiest
agers are particularly adept at shedding stress.

How Stress Works

To understand why it's so important to learn to manage stress,
you have to understand what happens inside your body when you
experience stress. The body rapidly mobilizes energy,
delivering glucose to your muscles. The heart rate, blood
pressure and breathing rate increase so that more oxygen can
be delivered more quickly throughout your body. Functions that
aren't needed in an emergency -- such as digestion, sex drive
and even your immune system -- are eventually suppressed.
Meanwhile, stress hormones that help dull pain and sharpen
your senses are released. Blood vessels constrict and clotting
factors increase to slow bleeding in case you are wounded.

An animal fleeing a predator, a soldier at war or a mother
fleeing a burning house with her child all benefit from the
fact that the body, under stress, responds by giving your
muscles, your heart and your lungs an added boost to help you
flee or fight for your life. Ideally, this stress response is
turned on for a short time, just long enough to get you out of
danger.

The problem is, it doesn't take much to switch on the stress
response. Worrying about a job deadline or fighting with your
spouse can both trigger it. If you're good at coping with
stress, then your stress response will eventually turn off.

But unremitting stress -- in a person who can't shed it -- leaves
the stress response in the "on" position. All those changes that
protect you in a moment of crisis suddenly turn on you. Now
you're just a person with unregulated blood sugar, high blood
pressure, blood clots, a depressed sex drive and an immune system
buckling under all the strain.

It sounds a lot like getting old.

Measuring Stress

Though many people consider stress an amorphous psychological
concept, its cumulative physiological effect can actually be
measured. A complex formula that involves blood pressure,
cholesterol, the variability of a person's heart rate and
stress-hormone levels (including cortisol, norepinephrine,
epinephrine and DHEA-S), as well as a person's waist-to-hip
ratio, all add up to something called the "allostatic load."
In studies, a high allostatic load was highly predictive of
mortality and signaled risk for heart disease, mental decline
and other problems.

Unfortunately, there's no way for the average person to get a
reading of his or her allostatic load. Scientists at Rockefeller
University in New York, which has led research on the concept,
have yet to find a corporate sponsor interested in transferring
this important research tool so it can be used by patients and
their doctors.

But even without a high-tech measurement of our stress burden,
most people are well aware of the stress in their lives. We do
know that poor, less-educated people tend to have a higher
allostatic load than highly educated, wealthy ones. People
who are sleep deprived or who don't exercise tend to have
higher allostatic loads than those with good sleep and
exercise habits. People who have strong social and family
relationships tend to have a lower allostatic load than loners.

To get an idea of how workplace stress can have long-term effects
on health and aging, consider the Whitehall studies, a series of
studies of British civil-service workers while Margaret Thatcher
was prime minister and her administration was pushing aggressively
to privatize government functions. In one government department,
scientists found notable increases in body-mass index, cholesterol,
stroke incident and need for sleep among the workers there. The
employees with the most authority and power posted the lowest
blood-pressure rates, while low-level workers, who lacked power
and feared most for their job security under privatization,
posted the highest blood-pressure rates.

"If you feel you're in control, you do a lot better than if you
lack control," says Rockefeller neuroendocrinologist Bruce
McEwen, an expert on allostatic load and author of "The End of
Stress as We Know It." He adds: "If you lack control, this
leads to being stressed out."

Another study shows that chronic stress increased risk for
catching  cold. One Carnegie Mellon University study surveyed
300 volunteers about stress and then injected them with a cold
virus. The people who had reported little chronic stress didn't
get sick -- their immune systems battled the virus. But
volunteers who had reported chronic stress that lasted for a
month or longer -- such as unemployment or family crisis -- fell
ill.

And in a series of stress studies by German researchers,
volunteers were asked to perform the stressful double whammy of
public speaking while performing difficult math problems.
Investigators took saliva samples each day to measure levels of
the stress hormone cortisol.

Initially, the task caused everyone to show signs of stress. But
most of the men began to relax by the second day and their stress
hormones leveled off as well. But about one-third of the men,
nervous about public speaking and plagued by low self-confidence,
continued to post high cortisol levels. High cortisol levels
have been linked with diabetes, heart disease and even obesity.

The Price of Being Alone

One reason successful agers may be better at handling stress is
that they tend to have a lot of social support. Successful agers
are not loners. People who age well tend to be close to extended
family and have a strong network of friends and social
relationships. Marriage in particular protects men from the
perils of aging. (Among women, it doesn't seem to matter if
they are married or not, as long as they have other close
relationships.)

The importance of family life and social relationships on
physical health has been shown consistently in both animal
and human studies. For instance, in a series of rat studies,
baby rats that were handled briefly in infancy produced fewer
stress hormones in adulthood than rats that were neglected.

In primate studies, relationships also make a difference in the
quality of old age. "One of the crappiest positions you can get
late in life is to be an old baboon in a troupe where you were
once a young baboon," says Dr. Sapolsky of Stanford. The reason:
Baboons, particularly high-ranking ones, spend their lives
terrorizing those with lower rankings. But rankings slide.
Powerful baboons get old, and the young baboons they once
terrorized eventually end up in a position to get revenge.

But there is one subset of male baboons that escapes the stress
of old age. These are the animals that spent their middle age
establishing close relationships with the females in the troupe.
Late in life, these baboons get harassed just as much as any
other baboon, but they stick around anyway, because they've got
a network of nice, female baboons that keep them company, groom
them and generally act as a buffer against what would otherwise
be a miserable life.

"Connectedness in old age is enormously important," Dr. Sapolsky
says.

The same thing that helps baboons age successfully also helps
humans. Study after study has shown that relationships make an
important difference in the ability to achieve old age. Even
centenarians, who have pretty much outlived most everyone they
know, have a history of strong social relationships.

Significantly, it isn't the practical support of relationships
-- having somebody to cook for you, for instance, or drive you
to a doctor's appointment -- that seems to make the most
difference.

The MacArthur Foundation study, which evaluated 4,000 older
people from Massachusetts, North Carolina and Connecticut,
focused on the one-third of the group that had the highest
mental and physical function at the outset. Researchers then
followed up with them at three and eight years into the study.
As it turned out, whether or not the study subjects had a
high frequency of emotional support -- meaning they spoke
and met often with family and friends -- was a powerful
predictor of who in the group ended up improving their
physical function over time. Having friends and family in
your life increases the likelihood that you will get out
more, keep moving and actually improve with age, rather
than decline.

Think Happy Thoughts

Personality traits such as optimism, adaptability and a
willingness to try new things also seem to be linked to
better aging. This became apparent in the Nun Study, which
for three decades has collected data from the School Sisters
of Notre Dame living in Mankato, Minn., as well as elsewhere
in the Midwest, East and South.

The study is important because extensive family, medical and
social history from the nuns is available. The goal of the Nun
Study is to determine the causes and prevention of Alzheimer's
disease and other brain diseases, as well as the mental and
physical disability associated with old age.

Among many notable findings has been a study of handwritten
autobiographies from 180 nuns, who wrote them, on average, at
the age of 22. The writings were scored for emotional content
and compared with survival rates from the age of 75 to 95.
What researchers noticed is that the nuns who wrote with the
most positive attitude at a very young age were 2½ times more
likely to be alive in late life than the sisters who came across
with a more negative point of view at a young age.

What's notable about the Nun Study, is that so much in these
women's lives is the same -- the food they eat, the quality of
medical care they receive, the life they lead -- and that's why
the differences are so striking. Consistently, the nuns who age
well are those with distinct personality traits such as a sense
of humor and adaptability. Many of these nuns still developed
illnesses and health problems associated with aging -- but those
who aged the most successfully were those who adapted to each
new challenge, including illness or disability.

"Everyone experiences normal day-to-day stress, and we all have
the same physiological response in terms of higher blood pressure
and higher stress hormones," says David Snowdon, the University
of Kentucky neurology professor who founded the Nun Study. "But
because of their positive outlook, our suspicion is that [the
sisters who have aged well] can come back down to their baseline
level quicker. They didn't grind on their stress. They had their
stress response, and they got over it."

Mental Decline

The Nun Study and others have also taught us that managing stress
may be particularly important in staving off mental decline.

Consider what happens to the brain during times of stress. For
about the first 30 minutes of a stressful event, the body boosts
glucose delivery to the brain. The short-term effect of this is
that senses are sharpened and memory is improved. But if the
stress lasts longer, the body calculates that all that extra
glucose is probably more urgently needed by muscles engaged in
fighting or fleeing. And so, even if you are actually just
sitting in a chair stressing out over a job deadline and you
really want that extra brainpower, the body shifts gears anyway
and stress hormones begin to inhibit glucose delivery to the
brain.

The impact of this is readily apparent in the hippocampus, the
part of the brain associated with memory and learning. Stress
hormones not only inhibit the development of neurons in the
hippocampus, but they kill neurons as well.

The end result of all this carnage is a smaller hippocampus.
Notably, strokes, long-term depression and trauma can all shrink
the hippocampus. And, as brain studies of the nuns after their
deaths have shown, a smaller hippocampus is also a tell-tale
signal of Alzheimer's disease.

This doesn't mean that everyone who experiences high stress will
develop Alzheimer's or that every person with Alzheimer's
developed the disease because of stress. But anyone who has
faced the stress of a family illness, divorce or job crisis
knows how mentally taxing such a life event can be. And based
on the science, it's increasingly clear that the aging brain is
not immune to the damaging effects of stress.

What Do We Do About It?

Clearly stress takes a significant physical toll on our bodies.
Complicating matters is the fact that not only does stress appear
to accelerate aging, but also the older we get, the longer it
takes for our bodies to turn off the stress response. So while
managing stress is important at any age, it's absolutely crucial
as we get older.

So how do we do it?

The first step, of course, is to cover the basics -- eat well,
manage your weight and exercise. If you take care of yourself,
you're essentially giving stress less to work with -- a
healthy body is more resilient against the onslaught of stress.

But that's not enough. At some point in life, everyone faces
chronic stress -- whether it's uncertainty at work, in a marriage
or about health. Successful agers have faced the same stressors
as the rest of us. They just have better coping skills. The good
news is that the rest of us can change and learn better coping
strategies.

SEEK CONTROL WHEN YOU CAN. The issue of control -- or the lack of
it -- is a common theme among stress researchers. Successful
agers typically feel in control of their day-to-day lives, but
they don't fret about issues they can't control. In his book
"Why Zebras Don't Get Ulcers," Dr. Sapolsky cites a nursing-home
study in which one group of residents was given far more control
over their daily lives. They were given responsibility for meals,
social activities and even caring for plants in their rooms. Soon,
those residents became noticeably more active, more engaged in
social activities and were generally happier. Death rates among
the residents given more control were half that of other
residents during the study period.

Animal studies show that losing control can also produce a
powerful physical reaction. In one experiment, rats are taught
to press a lever to avoid a mild shock. Remove the lever and
the rat becomes highly stressed. Simply disconnect the lever
and the rat is less stressed. Even though both rats are being
shocked, the rat with the nonworking lever feels more control
over the situation and produces fewer stress hormones than the
rat with no lever at all.

The lesson is that stress is easier to cope with -- and produces
fewer physical effects -- if we feel a sense of control. So while
work stress is inevitable, it's less harmful if you can control
various aspects of your day -- such as when you take a lunch
break or the type of projects you want to work on.

INFORMATION CAN RELIEVE STRESS. Stress doesn't take as much of
a toll if we can predict it. For instance, the nervous public
speakers loosened up after a few days of the task. They knew
what to expect, and they were less stressed. In rat studies,
animals given food on a predictable schedule become highly
stressed when given the same amount of food on a random schedule.

The lesson is to seek accurate information in the face of a
stressful situation. If you are worried about a job layoff
and uncertainty at work, arm yourself with information about
the job market and opportunities elsewhere. If you are facing
cancer, long-term fears are certain to cause stress, but you
can minimize the overall stress of the illness by learning
about treatments and side effects so you know what to expect.

KEEP FRIENDS AND FAMILY CLOSE. Baboons that take part in social
grooming have lower blood pressure. Breast-cancer patients who
join support groups have lower stress-hormone levels. And the
nervous public speakers had lower blood pressure if they had a
friend in the audience. Study after study shows social support
makes a measurable difference in how we cope with stress and
how we age.

EXERCISE YOU HATE WON'T HELP AS MUCH AS EXERCISE YOU LIKE.
Exercise is the solution for pretty much every health problem,
but it especially makes sense in dealing with stress. That's
because the stress response is all about boosting energy to
the muscles, so using those muscles during exercise is the
obvious outlet for releasing stress.

But exercise, by definition, is a form of stress. If you overdo
it, you're not helping yourself. At the same time, finding an
exercise you like not only will increase the likelihood you
will stick with it, but also may give you more benefit. Studies
show that rats freely allowed to trot on the exercise wheel
have lower stress hormones. But rats forced onto the wheel
are stressed by the experience and end up with a high stress
response.

In terms of exercise and stress reduction, it's also important
to know that the benefits of exercise disappear almost overnight.
"It's the exercise you're doing now that's important," Dr.
Snowden says. "If you were a college athlete, it's not going
to do anything for you in middle age."

The good news is that it's never too late to reap the benefits
of exercising. In fact, the older you are, the more immediate
benefit you get from exercise.

GET MORE SLEEP. When you start to lose sleep, your body responds
the way it always does in a crisis -- it activates the stress
response. It has been shown that sleep deprivation increases
allostatic load. Study subjects who get only four hours of
sleep for several nights had higher nighttime levels of cortisol
and blood glucose -- indicating higher allostatic load. But let
the participants sleep 10 to 12 hours a night and the allostatic
load disappears.

PICK AND CHOOSE YOUR STRESS RELIEF. In the end, everyone deals
with stress and aging differently. Stress-management classes,
meditation, massage, yoga, religious services -- all of them
can relieve stress in the right person and cause stress in the
wrong one. A person with a cynical outlook on life might find
a touchy-feely stress-management course discomfiting. Few
experiences are more stressful than trying to keep up with a
fast-paced aerobics class -- but some people love the experience.

"Even successful agers differ according to how they handle
their life experiences," Dr. Snowdon says. "It's something
individuals have to manage themselves. You know if you're
in trouble."

--Ms. Parker-Pope, who writes The Wall Street Journal's weekly
Health Journal column, served as contributing editor of this
report.

Write to Tara Parker-Pope at tara.parker-pope@wsj.com