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Bare-minimum
diet: Is long life the payoff?
By
Kathleen Fackelmann
USA TODAY Oct. 27, 2005
Khurram Hashmi has drastically cut the calories
he consumes - eating mostly salads and raw vegetables - in the
hopes of living a longer, better life.
But he's hungry almost all the time. "That's
something for me that has never gone away, but it is easier to
accept now," says Hashmi, 37. He says he used to cheat, but
not anymore. The hunger tells him that the diet's working, he
says.
The diet is not for everyone: Hunger and low libido
are facts of life for Hashmi and other followers. But they put
up with what amounts to a near-starvation diet because a slew
of studies has shown that mice and other lab animals that eat
a very low-calorie diet live about 30 percent longer than they
otherwise would. These studies also suggest that the diet protects
the body from age-related diseases such as diabetes.
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"It is the only nutritional regimen thought to retard aging,"
says Richard Weindruch at the University of Wisconsin-Madison.
His studies have suggested that middle-aged mice can start the
diet and still get the longevity benefit.
In
an ongoing study of monkeys, Weindruch has found that the very
low-calorie diet seems to shield these animals from type 2 diabetes,
a common disease of old age. None of the monkeys on the diet,
which are now about 70 in human terms, has developed diabetes.
Monkeys fed the usual lab chow already are developing this life-threatening
disease, he says.
But will the diet work for humans? Hashmi and
the 1,800 other members of the Calorie Restriction Society, a
non-profit group that advocates the diet, believe it will.
Hashmi, who runs his own Internet marketing business
from his home in Gardena, Calif., consumes about 1,800 calories
a day, far below the 2,400 consumed by the average American man.
He weighs 129 pounds, which on his 5-foot-11 frame looks gaunt.
He says the diet gives him enough energy for an active life that
includes a 4-mile-run every other day and 50-mile bike rides once
a week.
"I have lost some of the fat on my face,"
he says. "People think that it makes you look older."
But he's willing to put up with that because he
believes the diet will slow his aging and make him look younger
in the future.
More scientific evidence to support Hashmi's choice
arrived in April 2004.
Luigi Fontana, a researcher at Washington University
in St. Louis, and his colleagues reported results from a small
study of people who had been following the diet for up to 15 years.
All 18 people on the diet were members of the Calorie Restriction
Society. They reported consuming 1,100 to 1,950 calories a day,
depending on their height, weight and gender.
The team collected blood and measured biomarkers
that put people at risk of cardiovascular disease. They found
that the people on the diet, who were 35 to 82 years old, had
greatly reduced their risk of clogged arteries, which can lead
to heart attacks and stroke.
For example, when the team measured a type of
fat in the blood that often signals high cardiovascular risk,
they found that the people on the diet had levels that were lower
than 95 percent of people in their 20s. The average blood pressure
for people on the diet was 100/60 - about what is expected for
an average 10-year-old, Fontana says.
It comes with a cost
The study, which appeared in the Proceedings of
the National Academy of Sciences, still doesn't offer any proof
that the diet will push the human life span past normal limits.
Skeptics say flat-out it won't work the way it
does in mice.
John Phelan, an evolutionary biologist at UCLA,
constructed a math model of the diet and found that people who
drastically cut calories starting very early in life (and never
cheated) might live four to five years longer. The diet won't
push the maximum human life span much past 120, he says.
To Phelan, the diet's small benefit doesn't begin
to make up for the downside. He says mice on the diet, which provides
food at near-starvation levels, appear cranky. "If you take
the lid off the cage, they immediately bite you," he says.
And in addition to constant hunger, followers
say the diet can lower their libido. Hashmi, who is single, says
that although his libido is low for someone his age, he expects
to maintain an interest in sex throughout his life, into old age.
He says he was cranky when he first started the diet five years
ago. But Hashmi says his mood quickly stabilized after his body
adjusted to fewer calories.
Phelan once considered following the diet himself
but changed his mind when he plugged the numbers into his math
model. "It's a starvation diet for decades with very little
payoff," he says.
Following the diet also can be risky. People who
cut calories but eat mostly junk or highly processed food run
the risk of malnutrition, Fontana says.
People don't have to starve to get a benefit from
the diet, says Brian Delaney, president of the Calorie Restriction
Society. He says most Americans would gain by cutting out unnecessary
calories: They'd lose weight and - if the studies on rodents are
correct - they might age slightly more slowly.
That's what Hashmi is banking on. And that's why
he now carefully follows his diet. He considers everything he
eats - whole-grain muffins, vegetables and other foods loaded
with nutrients.
To Hashmi, the effort is worth it. He is betting
the diet will result in a longer life.
"If I can live to be 120 - that wouldn't
be bad."
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MATERIAL)
Other ways to stick around
If severely cutting your diet is too high a price
to pay for longer life, recent studies have suggested that the
average person can take these steps:
If you smoke, quit
Smoking accelerates the aging process and puts
people at risk of heart disease, emphysema and a long list of
cancers, including lung cancer.
Slim down
A recent study suggests the nation's obesity problem
could derail much of the past century's progress in extending
life. Obesity can trigger heart disease, diabetes and other life-threatening
conditions. "Getting rid of the fat may be the most potent
way to slow down the aging process," says Thomas Perls, director
of the New England Centenarian Study.
Work your body
Scientists already have identified a therapy that
keeps the body running at top capacity throughout life: exercise.
"It's the closest thing we have to a Fountain of Youth,"
says Jay Olshansky of the University of Illinois in Chicago. Regular
physical activity wards off heart disease, diabetes and maybe
Alzheimer's. It also seems to reverse some aspects of aging. For
example, lifting weights can help boost muscle mass, which declines
as people get older.
Load up on fruits and vegetables
There's no proof yet, but many experts believe
a diet rich in fruits and vegetables can help protect people from
a laundry list of age-related diseases, including heart disease
and cancer. Fruits and vegetables contain powerful anti-oxidants
that help neutralize damaging molecules called free radicals that
are thought to play a role in the aging process.
Avoid junk food
That includes white bread, white rice, soda, chips,
pastries and cakes. Instead, experts such as Luigi Fontana of
Washington University in St. Louis recommend foods that are packed
with nutrients, such as whole-grain bread, brown rice, fish and
nuts such as almonds or pecans.
Stay connected
Studies show a connection between social isolation
and depression and other diseases, says Christine Himes Fordyce
at the Group Health Cooperative in Seattle. People who volunteer,
join social groups or just maintain their ties with friends and
family seem to live longer, she says.
Don't sweat the small stuff
People who live a long time often seem to have
good coping skills, Perls says. They'll turn to prayer, meditation,
or even humor to help get them through a stressful situation.
Many studies have linked stress to a damaged immune system and
killer conditions such as heart disease.
Source:
http://www.azcentral.com/health/diet/articles/1026caloricrestriction-ON.html
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