Growing Old,
With the Bones in One Piece
By: Jane E. Brody
New York Times, November 13, 2001
Bones, once taken for granted, have
become a major health issue now that so many Americans are living well
into their 70's, 80's and beyond. For at least half of women and one in
eight men, bones are not bearing up as well as they should to sustain an
active, independent old age free of debilitating fractures.
As a result, osteoporosis — bones
seriously weakened by mineral loss — has become a household word, as
familiar to most people as cholesterol. And the pharmaceutical industry,
supplement makers and now food producers have responded with products
intended to keep Americans from breaking apart before their time on earth
is up.
But, judging from the questions I get
almost daily, many people are thoroughly confused about what may be good
and, even more important, what is bad for their skeletons. Unfortunately,
most of the queries come from people already on the cusp of osteoporotic
disaster, rather than from young people, who have the best hope of
preventing the disorder.
Trouble Starts Early
The best predictor of bone strength in
midlife and beyond is how well the skeleton was constructed in childhood
and adolescence. Maximum bone development ends in one's 20's, after which
bone loss gradually begins to exceed bone formation. Bone loss accelerates
rapidly in women after menopause.
But the habits of young Americans
portend a future epidemic of osteoporosis that far exceeds today's
problem, which already costs billions of dollars a year. Far too many
children have substituted soda, juices and other soft drinks for the
bone-building calcium and vitamin D in milk, and they rarely make up the
deficit by consuming calcium- rich vegetables or taking calcium
supplements. To make matters worse, millions of teenagers are smoking
cigarettes, another cause of bone loss.
Currently, about $10 billion is spent
each year to treat osteoporotic fractures. By the year 2020, experts
predict the cost will exceed $60 billion.
But forget cost for a moment. Let's talk
about quality of life, not to mention life itself. Ten million Americans
already have osteoporosis and another 18 million are at high risk for
developing it. Each year, this disease leads to 1.5 million broken bones,
including more than 700,000 vertebral fractures, 300,000 hip fractures,
200,000 wrist fractures and 300,000 fractures of other bones.
Vertebral fractures result in lost
height, a bent-over posture and often, chronic and debilitating pain. Of
those who break their hips, often in minor falls, half will never walk
independently again and a quarter will die of complications within a year.
Bones are constantly being broken down
and rebuilt. Preventing osteoporosis requires that the rebuilding keeps up
with or exceeds the breakdown. Rebuilding is undermined by smoking,
excessive alcohol consumption, insufficient dietary calcium, a shortage of
vitamin D, lack of weight-bearing or strength-building exercise and, in
women, a lack of estrogen. This last factor accounts for the rapid loss of
bone that occurs in women during the first five years after menstruation
ceases, but it can also affect young women who diet too strenuously or
exercise too vigorously and lose their periods as a result.
According to national nutrition surveys,
90 percent of adult women, 75 percent of men and teenagers and 70 percent
of younger children do not consume enough calcium to prevent osteoporosis.
The main dietary sources of this vital mineral are milk and other dairy
products. Several dark-green leafy vegetables, especially collard greens,
are also rich sources, but they are not among the nation's favorites.
Other good sources include sardines and canned salmon (eaten with the
bones). Many juices and cereals are now available with added calcium.
Young people from 9 through 18 should
consume 1,300 milligrams of calcium a day, adults 19 to 50 need at least
1,000 milligrams and those over 50 at least 1,200 milligrams (the amount
in a quart of low-fat milk), if not from foods then from supplements, like
calcium carbonate or calcium citrate. For postmenopausal women not taking
estrogen, 1,500 milligrams are recommended.
If calcium intake is adequate, moderate
amounts of caffeine and carbonated drinks seem to have no adverse effect
on the body's calcium stores.
For calcium to be properly used by the
body, adequate vitamin D is needed; this is mainly obtained from fortified
milk, and it is made in the skin in sunlight. Sun exposure on the face and
hands (without sunscreen) for 10 minutes a day is needed to foster
adequate production of vitamin D, but that kind of exposure is uncommon in
winter and among the elderly in every season. Recent studies suggest that
people over 65 should consume 800 International Units of vitamin D daily,
and that dosage would require taking a supplement.
Adequate protein — 63 grams a day for
men and 50 grams for women (more if from vegetable sources like soy) —
as well as vitamins C and K are also important to bone health. Keep in
mind, too, that without weight-bearing or strength-building exercise,
relatively little of the calcium consumed gets used by bones. That
inactivity explains the loss of bone mineral among astronauts while they
are weightless in space. Exercise also improves balance, flexibility and
muscle strength, all of which can help to prevent falls.
If you already have osteoporosis, you
may need help in formulating an appropriate exercise program. Ask your
doctor for a referral to a physical therapist, who can design an exercise
program to increase bone density and reduce stress on fragile bones.
For those seeking written guidance,
Margie Bissinger, a physical therapist, has produced the book
"Osteoporosis: An Exercise Guide," available for $9.95.
Drugs That Help
The osteoporosis crisis has spawned a
number of medicines designed to tip the balance in favor of bone building.
The leading one, for women, is estrogen replacement after menopause, which
may have to be maintained indefinitely to prevent rapid bone loss. Even
physically frail older women can achieve stronger bones by taking hormone
replacement, according to a recent study of 67 women 75 and older,
although there is no evidence yet that this regimen prevents fractures in
older women.
Since many women cannot or will not take
estrogen, other effective products have been developed. One is the
estrogen mimic raloxifene (marketed as Evista), which lacks estrogen's
adverse effects on the breast and uterus and may help prevent breast
cancer. Studies thus far have shown that raloxifene helps to prevent
vertebral fractures.
Two drugs called biphosphonates —
alendronate (Fosamax) and risedronate (Ac tonel) — are often prescribed
for people who already show signs of serious bone loss. They represent
another alternative for women who do not take estrogen replacement.
Fosamax has been shown to reduce the risk of fractures of the hip, spine
and wrists by as much as 50 percent and Actonel, a newer drug, also
reduced the incidence of new fractures in a two-year study of women with
osteoporosis.
These two drugs require adherence to a
strict regimen to avoid damage to the esophagus and to assure absorption.
They must be taken first thing in the morning on an empty stomach and with
a large glass of water, after which you must stand or sit upright and not
eat or drink anything else for at least 30 minutes.
A third option is salmon calcitonin, a
hormone that inhibits bone resorption. But it is less effective than the
other drugs. It is available as a nasal spray and approved for the
treatment of osteoporosis, especially painful vertebral fractures. A
number of other products, including parathyroid hormone, are now being
studied. So stay tuned.
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