Preventing
Bone Loss
If
hereditary factors or a small frame size puts you at risk for
osteoporosis, you can't do much about it—but that's all the
more reason to take preventive steps. The best time to begin a
program of prevention is in childhood and then continue it throughout
your life. In your twenties and early thirties, bone density is
on the increase. The more bone you build early in life, the better
you will be able to withstand bone loss later. But even if you've
waited until your forties, fifties, or sixties, there's still
plenty of reason to follow this preventive program:
•
Make weight-bearing exercise part
of your daily life. That means walking,
running, cycling, dancing, or weight-lifting—or activities
such as housework or mowing the grass. Swimming and yoga are
not weight-bearing exercises, and thus don't build bones, though
they have other benefits. Exercise should be part of your life
at all stages, but a high level of physical activity is particularly
important as you grow older.
•
Consume enough calcium. Besides
building strong bones and maintaining bone density and strength,
calcium also plays a role in regulating your heartbeat and other
vital functions. The recommended dietary allowance for adults
is 1,000 milligrams daily, except for women over 50 and men
over 65, who should aim for 1,500 milligrams daily, from food
and supplements. A cup of milk provides 300 milligrams of calcium;
8 ounces of yogurt, 300 to 450 milligrams. Cottage cheese, by
the way, has little calcium. Most hard cheeses have about 200
milligrams per ounce, but are also high in sodium, cholesterol,
and saturated fat. The vitamin D added to milk and the lactose
naturally in milk and dairy products are thought to aid in the
absorption of calcium.
Many dark green leafy vegetables are rich in calcium. A half-cup
serving of cooked broccoli, beet greens, or kale has about 90
milligrams. Herring, salmon, and sardines—if eaten with
the small bones—are also good calcium sources. Tofu (soybean
curd) often contains a fair amount of calcium, too. But the
best sources of calcium for most Americans, who usually don't
eat much kale, beet greens, or fish bones, remain low-fat or
nonfat dairy products.
•
If you smoke, stop.
Not only for the strength of your bones, but for your general
health and well-being.
•
If you drink, drink only lightly
or moderately. Light to moderate drinking
is defined as an average of no more than two drinks a day. A
drink is defined as five ounces of wine, 12 ounces of beer,
or 1.5 ounces of 80-proof liquor (all contain about half an
ounce of pure alcohol).
•
Consider hormone replacement therapy
(HRT) if you are menopausal. This
consists of low-dose estrogen and progestin treatments that
can unquestionably slow bone loss and prevent fractures as well
as reduce hot flashes and other common menopausal symptoms.
The added progestin also reduces the risk of endometrial cancer.
HRT probably protects against heart disease, though the evidence
remains controversial. (It's estrogen, not the combination of
estrogen with progestin, that's known to be protective.) HRT,
if used to prevent osteoporosis, should be started at menopause
for maximum effect.
But menopause is not a medical condition that automatically requires
drugs. Some women do very well without HRT, which has its downside,
too. It may increase the risk of breast cancer, though the evidence
isn't yet clear. Still, women who have had breast cancer should
not undergo HRT. Those with migraine headaches, diabetes, and
other disorders are sometimes advised against it. All women should
be informed about HRT and, at menopause, should discuss the pros
and cons with their physicians.
In particular, if you have additional risk factors for osteoporosis
(see list below), you should consider HRT. But whether you take
it or not, you should address the risk factors that you can modify:
begin an exercise program if you're sedentary, increase your calcium
intake, don't smoke, and limit your alcohol intake.
If you are taking oral contraceptives, you'll be pleased to learn
that recent studies have shown that their use has a notable positive
effect on bone density, independent of other beneficial factors
such as calcium intake and exercise.
Calcium supplements: the new news is good news
It's
better to get the calcium you need from food than from pills because
food also contains other nutrients you need—including those,
such as vitamin D, magnesium, and boron, that are important in
building bone. But many women, especially older women who tend
not to eat dairy products, just don't get enough calcium.
There used to be serious questions about whether calcium supplements
do any good. But research has made it clear that supplements can
help—even in women well past menopause who are not on hormone
replacement therapy—helping to slow bone loss and even increase
bone density, thus reversing osteoporosis.
How much calcium is enough? The minimal healthy intake of calcium
for postmenopausal women is 1,500 milligrams daily, and more would
be even better. The best plan seems to be to get at least 750
milligrams of calcium from your diet. Skim milk and nonfat yogurt
are excellent sources because they also contain vitamin D, which
is necessary for calcium absorption. A pint of milk together with
a cup of broccoli or some other leafy green vegetable would supply
this much calcium. Then bring the total to 1,750 milligrams by
taking a 1,000-milligram supplement. There's no convincing evidence
so far that one kind of calcium supplement is significantly better
than another.
What puts you at risk: a checklist
•
Increasing age.
•
Being female.
By age 65, the average man still has 91% of his bone mass, but
the average woman has only about 74%.
•
Being chronically underweight
or having a slight frame.
•
Being Caucasian or Asian
(usually small-boned).
•
Having osteoporosis in the family.
•
A poor diet,
low in vitamins and minerals, especially calcium.
•
Being sedentary and
lack of weight-bearing exercise.
•
Smoking. In
women this lowers the estrogen content of the blood, thus weakening
the bones. Smoking is particularly dangerous for women who have
other risk factors for osteoporosis.
•
Heavy drinking. It's
not known why heavy drinking weakens the bones—perhaps
because heavy drinkers often eat a poor diet.
•
Long-term use of certain medications.
Some people with asthma and rheumatoid arthritis take cortisone
for long periods, which can diminish bone strength. So can long-term
use of thyroid hormones, which are sometimes used to treat obesity,
although most physicians do not recommend them for this purpose.
Reference
Source 98
