When most people think of bones, what comes to mind are the lifeless,
dead bones of skeletons. But, bone is actually a dynamic, living
tissue.
Healthy bones are dependent on an intricate interplay of many
nutritional and hormonal factors. In the human body, there is a
constant
process of breaking down and remaking of bones. When the rate of bone
breakdown exceeds that of bone manufacture it can result in a condition
known as "osteoporosis." Literally, the word osteoporosis means "porous
bone." Osteoporosis affects more than twenty million people in the
United States including one out of four postmenopausal women.1
What exactly causes osteoporosis?
Normally there is a decline in bone mass after the age of forty in both
sexes (about two percent loss per year), but women are at a much
greater
risk for osteoporosis because of lower bone density prior to age forty.
Osteoporosis involves both the mineral (inorganic) and nonmineral
(organic matrix, composed primarily of protein) components of bone.
This
is the first clue that there is more to osteoporosis than a lack of
dietary calcium. In fact, lack of dietary calcium in the adult results
in a separate condition known as osteomalacia, or "softening of the
bone." The two conditions, osteomalacia and osteoporosis, are different
in that in osteomalacia there is only a deficiency of calcium in the
bone. In contrast, in osteoporosis there is a lack of both calcium and
other minerals, as well as a decrease in the nonmineral framework
(organic matrix) of the bone. Little attention has been given to the
important role that this organic matrix plays in maintaining bone
structure.
Table 1 - Major Risk Factors for Osteoporosis in Women
Family history of osteoporosis
Gastric or small-bowel resection
Heavy alcohol use
Hyperparathyroidism
Hyperthyroidism
Inactivity
Leanness
Long-term glucocorticosteroid therapy
Long-term use of anticonvulsants
Low calcium intake
Nulliparity (never having been pregnant)
Postmenopause
Premature menopause
Short stature and small bones
Smoking
White or Asian race
Where does the bone loss in osteoporosis occur?
Although the entire skeleton may be involved in postmenopausal
osteoporosis, bone loss is usually greatest in the spine, hips, and
ribs. Since these bones bear a great deal of weight, they are then
susceptible to pain, deformity, or fracture. At least 1.5 million
fractures occur each year as a direct result of osteoporosis, including
250,000 hip fractures, the most catastrophic of fractures. Hip fracture
leads to death (both directly and indirectly as a result of long-term
hospital stays) in twelve to twenty percent of cases and precipitates
long-term nursing home care for half of those who survive. Nearly
one-third of all women and one-sixth of all men will fracture their
hips
in their lifetime.2
How do I determine my bone density?
There are several techniques to measure bone density. The one that I
recommend is known as dual energy X-ray absorptiometry (DEXA).3 In
addition to providing the most reliable measurement of bone density,
the
DEXA test also exposes a person to considerably less radiation than
other X-ray procedures for measuring bone density. In the DEXA exam,
the
measurements will usually be of both the hip and the lumbar spine. I
recommend that women of high risk (see table 1) get a baseline
bone-density measurement and then monitor the rate of bone loss using a
urine test known as OsteoCheck (available through www.bodybalance.com).
In other words, the DEXA test can be used to measure bone density,
while
the OsteoCheck can be used to measure the rate of bone loss.
The OsteoCheck measures the urine levels of a compound linked to bone
breakdown (deoxypyridinium). The OsteoCheck can be used to monitor the
rate of bone loss and the success (or failure) of therapy. The
OsteoCheck provides faster feedback than DEXA, which can take up to two
years to detect a therapeutic response. For more information on the
OsteoCheck test, see www.bodybalance.com.
What can be done to maintain bone health and prevent osteoporosis?
Recently there has been an incredible push for increasing dietary
calcium intake to prevent osteoporosis. While this appears to be sound
medical advice for many, osteoporosis represents much more than a lack
of dietary calcium. It is a complex condition involving hormonal,
lifestyle, and nutritional factors. A comprehensive plan that addresses
these factors offers the greatest protection against developing
osteoporosis. The primary goals in the treatment and prevention of
osteoporosis are to:
Preserve adequate mineral mass,
Prevent loss of the protein matrix and other structural components of
bone,
Assure optimal repair mechanisms to remodel damaged areas of bone.
Achieving these goals requires adoption of lifestyle, dietary, and
nutritional supplementation practices to build healthy bones.
What lifestyle factors are important for maintaining bone health?
Certain lifestyle factors are extremely important to bone health. For
example, coffee, alcohol, and smoking cause a negative calcium balance
(more calcium being lost than taken in) and are associated with an
increased risk of developing osteoporosis, while regular exercise
reduces that risk.5,6 In fact, exercise is the most critical factor for
maintaining healthy bones. Physical exercise, consisting of one hour of
moderate activity three times a week, has not only been shown to
prevent
bone loss, but actually increase bone mass in postmenopausal women.
What are the key dietary factors to maintain bone health?
Many general dietary factors have been suggested as a cause of
osteoporosis: low-calcium-high-phosphorus intake, high-protein diet,
high-acid-ash diet, high salt intake, and trace-mineral deficiencies,
to
name a few.8,9 Considering that the average American consumes 150 grams
of sucrose in one day, along with other refined simple sugars,
carbonated beverages loaded with phosphates, and large quantities of
protein, it is little wonder that there are so many people suffering
from osteoporosis in this country. When lifestyle factors are also
taken
into consideration, it is apparent why osteoporosis has become a major
medical problem.
One of the best things you can do for your bone health is to stay away
from soft drinks. Soft drinks have long been suspected of leading to
lower calcium levels and higher phosphate levels in the blood. When
phosphate levels are high and calcium levels are low, calcium is pulled
out of the bones. The phosphate content of soft drinks like Coca-Cola
and Pepsi is very high, and they contain virtually no calcium. The high
phosphate level is required for dissolving the sugar and contributing
to
the taste. It appears that increased soft-drink consumption is a major
factor that contributes to osteoporosis. The United States ranks first
among countries in soft-drink consumption. The per-capita consumption
of
soft drinks is in excess of 150 quarts per year, or about 3 quarts per
week.
What about milk?
Contrary to what the advertisements from the dairy industry tell us,
milk consumption may not lead to strong bones. While numerous clinical
studies have demonstrated that calcium supplementation can retard bone
loss, the data is inconclusive in regards to a high dietary calcium
intake from milk and prevention of osteoporosis and bone fractures. One
of the first clues that milk consumption may not be that beneficial for
bone health is data showing that that countries with the highest dairy
intake have the highest rate of hip fractures per capita.
In analyzing data from the Nursesí Health Study, a stud involving
77,761
women, researchers found no evidence that higher intakes of milk
actually reduced fracture incidence.10 In fact, women who drank two or
more glasses of milk per day had a relative risk 45% for hip fracture
compared to women consuming one glass or less per week. In other words,
the more milk that was consumed the more likely a woman would
experience
a hip fracture. This data simply does not support the idea that "every
body needs milk."
Is calcium supplementation important in preventing and treating
osteoporosis?
Yes, absolutely. But, preventing and reversing osteoporosis involves
much more than calcium. Bone is dependent on a constant supply of many
nutrients. A deficiency of any of a number of nutrients such as boron,
magnesium, vitamin K, and others will adversely affect bone health. To
truly support bone health in my patients at high risk for osteoporosis,
along with a high potency multiple vitamin and mineral formula, I
recommend additional bone building nutrients such as calcium (to bring
total daily supplement levels to 1,000 mg), boron, magnesium, and folic
acid. In my patients with existing osteopororis, I recommend adding
ipriflavone (Ostivone) to the program.
Ipriflavone has shown excellent results in helping to prevent further
bone loss. And, along with the calcium and other important nutrients
ipriflavone can actually help rebuild bone.
When should a woman start taking calcium?
There is a strong correlation between pre-menopausal bone density and
the risk of osteoporosis. In other words, how dense the bones are prior
to menopause is a significant factor in determining whether or not a
woman develops osteoporosis. That being the case, building strong bones
should be a lifelong goal beginning in childhood. However, the reality
is that most women probably are not that concerned about osteoporosis
until a couple of years before menopause (the perimenopause).
Fortunately, even taking calcium just prior to the onset of menopause
has been shown to produce considerable benefit in increasing bone
density. For example, in a two-year study 214 women near the age of
menopause (perimenopausal) received either 1,000 or 2,000 mg of calcium
or a placebo.11 While the control group actually lost 3.2% of their
bone
density of their spine, the calcium-treated groups increased the
density
by 1.6% (there was no difference between the two calcium groups). These
results highlight the importance of calcium supplementation prior
menopause in the battle against osteoporosis.
Can calcium supplementation increase bone density in postmenopausal
women with osteoporosis?
Not by itself. In women who have passed through menopause,
supplementation of calcium has only been shown to be effective in
reducing bone loss. Although on its own, calcium supplementation does
not completely halt the process, it does slow the rate down by at least
30 to 50% and offers significant protection against hip fractures.12-14
While menopausal and postmenopausal women are often told that without
hormone replacement therapy they will most definitely get osteoporosis,
several studies provide strong evidence on the inaccuracy of this
commonly held view. Although calcium alone is less effective than when
it is combined with estrogen, because calcium supplementation carries
with it no significant health risks this study reinforces the opinion
that hormone replacement therapy should definitely be reserved for
women
at significant risk for osteoporosis.
For women with confirmed osteoporosis, I recommend strongly that they
discuss treatment options with their physicians. I also recommend,
regardless of the treatment chosen, that proper monitoring with
OsteoCheck levels be performed to validate effectiveness of treatment.
Ipriflavone (Ostivone) is an exciting natural approach to maintaining
bone health. Several double-blind studies have shown that this
naturally-occurring flavonoid (plant pigment) can dramatically halt the
progression of bone loss when used in combination with 1,000 mg of
calcium.15-17 The typical dosage of ipriflavone is 200 mg three times
daily.
What is an Effective Dosage of Calcium?
The effectiveness of calcium supplementation at a particular dosage is
ultimately dependent upon the womanís diet and lifestyle. As
repeatedly
stated throughout this article, bone health and osteoporosis
treatment/prevention involves much more than calcium. That being said,
an effective dosage for supplemental calcium is 600 to 1,200 mg per day
for most women. If there is significant bone loss, the dosage may need
to be in the 1,000 to 1,500 range.
What is the Best Form of Calcium?
The best form of calcium is certainly neither oyster shell, bone meal,
or calcium hydroxyapatite. Studies have indicated that these calcium
supplements may contain substantial amounts of lead or have a lower
absorption profile compared to other forms of calcium.18 I would
recommend staying away from these forms of calcium.
Calcium bound to citrate and other Krebs cycle intermediates such as
fumarate, malate, succinate, and aspartate appears to be the best
overall form of calcium although refined calcium carbonate is still an
excellent form for the majority of women. The additional benefit with
using minerals bound to Krebs cycle intermediates is that over 95% of
the Krebs cycle intermediates ingested are used to produce cellular
energy with the remainder being excreted in the urine where they may
act
to prevent kidney stone formation. The Krebs cycle intermediates
fulfill
every requirement for an optimum calcium chelating agent: (a) they are
easily ionized, (b) they are almost completely degraded, (c) they have
it virtually no toxicity, and (d) they have been shown to increase the
absorption of not only calcium, but other minerals as well.
In short, refined calcium carbonate has the lowest lead content, but
calcium bound to Krebs cycle compounds appear to be better absorbed
especially in women with low gastric acid output than other forms of
calcium. The problem with calcium supplements bound to the Krebs cycle
compounds is their bulk ñ it basically requires three to four times as
many capsules or tablets to provide the same level of calcium compared
to calcium carbonate sources. Providing a combination of calcium
carbonate and Krebs cycle calcium appears to be a reasonable solution.
What about calcium hydroxyapatite?
Although this form of calcium - basically a purified bone meal -
receives a lot of hype, there is little science to support
manufacturers
claims that it is a superior form of calcium for bone health. Quite the
contrary. What scientific studies show is that among calcium
supplements
tested for absorption, this form tested at 20% absorption compared to
30% for either calcium carbonate or calcium citrate in one study and
was
the poorest absorbed form out of five commercially available forms in
another.19,20 Clearly these results do not support the marketing hype
for calcium hydroxyapatite.
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Lindsay R: The burden of osteoporosis: Cost. Am J Med
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Chestnut CH, et al.: Hormone replacement therapy in postmenopausal
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Aloia JF, Cohn SH, Vaswani A, et al.: Risk factors for postmenopausal
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Feskanich D, et al.: Milk, dietary calcium, and bone fractures in
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Elders PJM, et al.: Long-term effect of calcium supplementation on bone
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Reid IR, et al.: Long-term effects of calcium supplementation on bone
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Devine A, et al.: A 4-year follow-up study of the effects of calcium
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Adami S, et al.: Ipriflavone prevents radial bone loss in
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Agnusdei D, et al.: A double-blind, placebo-controlled trial of
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Passeri M, et al.: Effects of 2-year therapy with ipriflavone in
elderly
women with established osteoporosis. Ital J Miner Electrolyte Metab
9:137-44, 1995.
Bourgoin BP, et al.: Lead content in 70 brands of dietary calcium
supplements. Am J Public Health 83:1155-60, 1993.
Carr CJ and Shangraw RF: Nutritional and pharmaceutical aspects of
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Deroisy R, et al.: Acute changes in serum calcium and parathyroid
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