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Explorers once searched
for the fountain of youth, and old legends tell of magic potions that
keep people young. The ancient questions--Why do people grow old? How
can we live longer?--still fascinate people, including the scientists
who study aging (gerontologists). But their most important question is
this: how can people stay healthy and independent as they grow older?
Recently, researchers
have begun to find certain chemicals in our bodies that may someday answer
these questions. As a result, some stores and catalogs now sell products
that are similar to these chemicals. However, the advertising claims that
these products can extend life are very much exaggerated. Here are some
of the chemicals being studied and what scientists have learned about
them so far.
Antioxidants.
These are natural substances that may help prevent disease. Antioxidants
fight harmful molecules called oxygen free radicals, which are created
by the body as cells go about their normal business of producing energy.
Free radicals also come from smoking, radiation, sunlight, and other factors
in the environment.
Some antioxidants,
such as the enzyme SOD (superoxide dismutase), are produced in the body.
Others come from food; these include vitamin C, vitamin E, and beta carotene,
which is related to vitamin A.
The body’s antioxidant
defense system prevents most free-radical damage, but not all. As people
grow older, the damage may build-up. According to one theory of aging,
this build-up eventually causes cells, tissues, and organs to break down.
There is some evidence
to support this theory. For instance, the longer an animal lives, the
more antioxidants it has in its body. Also, some studies show that antioxidants
may help prevent heart disease, some cancers, cataracts, and other health
problems that are more common as people get older.
Most experts think
that the best way to get these vitamins is by eating fruits and vegetables
(five helpings a day) rather than by taking vitamin pills. SOD pills have
no effect on the body. They are broken up into different substances during
digestion. More research is needed before specific recommendations can
be made.
DNA and RNA.
DNA (deoxyribonucleic acid) is the material in every cell that holds the
genes. Every day some DNA is damaged and most of the time it is repaired.
But more and more damage occurs with age, and it may be that DNA repair,
never 100 percent perfect, falls further and further behind. If so, the
damage that does not get repaired and builds up could be one of the reasons
that people age.
As a result, pills
containing DNA and RNA (ribonucleic acid, which works with DNA in the
cells to make proteins) are on the market. But DNA and RNA are like SOD
tablets. When they are taken by mouth, they are broken down into other
substances and cannot get to cells or do any good.
DHEA. Short
for dehydroepiandrosterone, DHEA is a hormone that has turned back some
signs of aging in animals. When given to mice, it has boosted the immune
system and helped prevent some kinds of cancer.
DHEA travels through
the body in the blood in a special form, called DHEA sulfate, which turns
into DHEA when it enters a cell. Levels of DHEA sulfate are high in younger
people but tend to go down with age.
Substances labeled
DHEA are being sold as a way to extend life, although no one knows whether
they are effective.
Other Hormones.
In a recent study with a small number of men, injections of growth hormone
boosted the size and strength of the men’s muscles and seemed to reverse
some signs of aging. Now, larger studies are testing growth hormone and
other hormones, such as estrogen and testosterone, to find out whether
they can prevent weakness and frailty in older people.
However, it is much
too early to know whether any of these hormones will work. There could
be problems. Moreover, the side effects of hormones could be very serious;
high amounts of some hormones have been linked to cancer.
Ten Tips for Healthy
Aging
No known substance can extend life, but the chances of staying healthy
and living a long time can be improved:
- Eat a balanced
diet, including five helpings of fruits and vegetables a day.
- Exercise regularly
(check with a doctor before starting an exercise program).
- Get regular health
check-ups.
- Don’t smoke (it’s
never too late to quit).
- Practice safety
habits at home to prevent falls and fractures. Always wear your seatbelt
in a car.
- Stay in contact
with family and friends. Stay active through work, play, and community.
- Avoid overexposure
to the sun and the cold.
- If you drink, moderation
is the key. When you drink, let someone else drive.
- Keep personal and
financial records in order to simplify budgeting and investing. Plan
long-term housing and money needs.
- Keep a positive
attitude toward life. Do things that make you happy.
The Bottom Line
Currently no treatments, drugs, or pills are known to slow aging or extend
life in humans. Check with a doctor before buying pills or anything else
that promises to slow aging, extend life, or make a big change in the
way you look or feel.
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