The bone-thinning condition called osteoporosis can lead to small and
not-so-small fractures. Although many people think of calcium in the
diet as good protection for their bones, this is not at all the whole
story. In fact.. in a 12-year Harvard study of 78,000 women, those who
drank milk three times a day actually broke more bones than women who
rarely drank milk. Similarl
y, a 1994
study of elderly men and women in Sydney, Australia, showed that higher
dairy product consumption was associated with increased fracture risk.
Those with the highest dairy product consumption had approximately
double the risk of hip fracture compared to those with the lowest
consumption.
To protect your bones you do need calcium in your diet.. but you also need to keep calcium in your bones.
How to Get Calcium into Your Bones
1. Get calcium from greens, beans, or fortified foods.
The most healthful calcium sources are green leafy vegetables and
legumes, or "greens and beans" for short. Broccoli, Brussels sprouts,
collards, kale, mustard greens, Swiss chard, and other greens are loaded
with highly absorbable calcium and a host of other healthful nutrients.
The exception is spinach, which contains a large amount of calcium but
tends to hold onto it very tenaciously, so that you will absorb less of
it.
Beans are humble foods, and you might not know that they
are loaded with calcium. There is more than 100 milligrams of calcium in
a plate of baked beans. If you prefer chickpeas, tofu, or other bean or
bean products, you will find plenty of calcium there, as well. These
foods also contain magnesium, which your body uses along with calcium to
build bones.
If you are looking for a very concentrated
calcium source, calcium-fortified orange or apple juices contain 300
milligrams or more of calcium per cup in a highly absorbable form. Many
people prefer calcium supplements, which are now widely available.
Dairy products do contain calcium, but it is accompanied by animal
proteins, lactose sugar, animal growth factors, occasional drugs and
contaminants, and a substantial amount of fat and cholesterol in all but
the defatted versions.
2. Exercise, so calcium has somewhere to go.
Exercise is important for many reasons, including keeping bones strong.
Active people tend to keep calcium in their bones, while sedentary
people lose calcium.
3. Get vitamin D from the sun, or supplements if you need them.
Vitamin D controls your body's use of calcium. About 15 minutes of
sunlight on your skin each day normally produces all the vitamin D you
need. If you get little or no sun exposure, you can get vitamin D from
any multiple vitamin. The Recommended Dietary Allowance is 600 IU (5
micrograms) per day. Vitamin D is often added to milk, but the amount
added is not always well controlled.
How to Keep It There
It's not enough to get calcium into your bones. What is really critical is keeping it there. Here's how:
1. Reduce calcium losses by avoiding excess salt.
Calcium in bones tends to dissolve into the bloodstream, then pass
through the kidneys into the urine. Sodium (salt) in the foods you eat
can greatly increase calcium loss through the kidneys.3 If you reduce
your sodium intake to one to two grams per day, you will hold onto
calcium better. To do that, avoid salty snack foods and canned goods
with added sodium, and keep salt use low on the stove and at the table.
2. Get your protein from plants, not animal products.
Animal protein—in fish, poultry, red meat, eggs, and dairy
products—tends to leach calcium from the bones and encourages its
passage into the urine. Plant protein—in beans, grains, and
vegetables—does not appear to have this effect.4
3. Don't smoke.
Smokers lose calcium, too. A study of identical twins showed that, if
one twin had been a long-term smoker and the other had not, the smoker
had more than a 40 percent higher risk of a fracture.5
American
recommendations for calcium intake are high, partly because the meat,
salt, tobacco, and physical inactivity of American life leads to overly
rapid and unnatural loss of calcium through the kidneys. By controlling
these basic factors, you can have an enormous influence on whether
calcium stays in your bones or drains out of your body.
Hormone Supplements Have Serious Risks
Some doctors recommend estrogen supplements for women after menopause
as a way to slow osteoporosis, although the effect is not very great
over the long run, and they are rarely able to stop or reverse bone
loss.
Many women find these hormones distasteful because the
most commonly prescribed brand, Premarin, is made from pregnant mares'
urine, as its name suggests. What has many physicians worried is the
fact that estrogens increase the risk of breast cancer. The Harvard
Nurses' Health Study found that women taking estrogens have 30 to 80
percent more breast cancer, compared to other women.6
Moreover,
Premarin may aggravate heart problems. In a study of 2,763
postmenopausal women with coronary disease followed for an average of
four years, there were as many heart attacks and related deaths in women
treated with the combined regimen of estrogens and a progesterone
derivative, as with placebo, but the coronary problems occurred sooner
in women taking hormones. Hormone-treated women were also more likely to
develop dangerous blood clots and gallbladder disease.7 Controlling
calcium losses is a much safer strategy.
Reversing Osteoporosis
If you already have osteoporosis, you will want to speak with your
doctor about exercises and perhaps even medications that can reverse it.
Osteoporosis in Men
Osteoporosis is less common in men than in women, and its causes are
somewhat different. In about half the cases, a specific cause can be
identified and addressed:8
■Steroid medications, such as
prednisone, are a common cause of bone loss and fractures. If you are
receiving steroids, you will want to work with your doctor to minimize
the dose and to explore other treatments.
■Alcohol can weaken your
bones, apparently by reducing the body's ability to make new bone to
replace normal losses. The effect is probably only significant if you
have more than two drinks per day of spirits, beer, or wine.
■A
lower than normal amount of testosterone can encourage osteoporosis.
About 40 percent of men over 70 years of age have decreased levels of
testosterone.
In many of the remaining cases, the causes are
excessive calcium losses and inadequate vitamin D. The first part of the
solution is to avoid animal protein, excess salt and caffeine, and
tobacco, and to stay physically active in order to reduce calcium
losses. Second, take vitamin D supplements as prescribed by your
physician. The usual amount is 600 IU (5 micrograms) per day, but it may
be doubled if you get no sun exposure at all. If you have trouble
absorbing calcium due to reduced stomach acid, your doctor can recommend
hydrochloric acid supplements.
Calcium and Magnesium in Foods (milligrams)
Food Source
Calcium
Magnesium
Collards (1 cup, boiled)
358
52
Orange juice, calcium-fortified (1 cup)
350*
--
Oatmeal, instant (2 packets)
326
70
Figs, dried (10 medium)
269
111
Tofu, calcium-set (1/2 cup)
258
118
Spinach (1 cup, boiled)
244
158
Soybeans (1 cup, boiled)
175
148
White beans (1 cup, boiled)
161
113
Mustard greens (1 cup, boiled)
150
20
Navy beans (1 cup, boiled)
128
107
Vegetarian baked beans (1 cup)
128
82
Great northern beans (1 cup, boiled)
121
88
Black turtle beans (1 cup, boiled)
103
91
Swiss chard (1 cup, boiled)
102
152
Broccoli (1 cup, boiled)
94
38
Kale (1 cup boiled)
94
24
English muffin
92
11
Butternut squash (1 cup, boiled)
84
60
Pinto beans (1 cup, boiled)
82
95
Chick peas (1 cup, canned)
80
78
Sweet potato (1 cup, boiled)
70
32
Green beans (1 cup, boiled)
58
32
Barley (1 cup)
57
158
Brussels sprouts (8 sprouts)
56
32
Navel orange (1 medium)
56
15
Raisins (2/3 cup)
53
35