Larsen Family Chiropractic
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Feb 17 2006
Little benefit
taking calcium, vitamin D
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BOSTON (AP) — The biggest study ever of calcium and vitamin D supplements
for older women showed they offered only limited protection against
broken bones, raising questions over what has been an article of
faith among doctors and nutritionists.
The supplements
seemed to reduce the risk of broken hips in women over 60 and also
helped those who took the supplements
most regularly. But as to preventing bone fractures overall, vitamin
D and calcium flunked in these healthy women.
One of the researchers, Dr. Norman Lasser at New Jersey Medical
School, said the study is “not as ringing an endorsement of
calcium as one might like.”
Even so, many experts said they would stand behind federal
guidelines recommending the supplements,
if needed, to meet standard intake of calcium and vitamin D.
“There’s probably a small benefit,” said Dr. Joel Finkelstein,
of Massachusetts General Hospital, who wrote an editorial in the New
England Journal of Medicine where the study appeared Thursday.
“It’s a good start, but women at higher risk need to know it’s
not enough.”
The findings were an offshoot of a big national study of diet and
hormone therapy known as the Women’s Health Initiative.
Osteoporosis touches an estimated 10 million Americans, making their
bones prone to break. One of two women will suffer such a fracture
in her lifetime.
For women over age 50, U.S. federal guidelines recommend 1,200
milligrams of bone-building calcium and 400-600 international units
of vitamin D daily from diet and, if needed, supplements.
The seven-year study of 36,282 women ages 50 to 79 gave half the
participants 1,000 milligrams of calcium and 400 units of vitamin D,
while the other half took dummy pills.
However, many were also taking their own supplements
before the research began, and they were allowed to keep doing so,
whether they were assigned to the test group or the comparison
group. These extra supplements
may have helped the women stay healthy but ironically diluted the
findings, since any benefit is harder to show against a backdrop of
fewer fractures. Also, women in the study were taking hormone pills,
likely further cutting the number of fractures.
The study showed better hip bone density in the group given supplements,
but they ranked no better statistically in avoiding fractures of all
kinds. However, women over age 60 reduced their chances of hip
fracture by 21 per cent with the supplements.
Many women sometimes missed their daily dose — a common phenomenon
in real-world testing — but those who took their supplements
most faithfully lowered their risk by 29 per cent.
“We still do believe ... that maintaining an adequate calcium
intake will lay the foundation for bone health,” said lead author
Dr. Rebecca Jackson at Ohio State University.
Dr. Bess Dawson-Hughes, a Tufts University vitamin expert who helped
shape the dietary guidelines, said they should remain unchanged for
now. She largely dismissed the overall negative finding.
“You put people who don’t need it together with people who
aren’t taking it, and you find nothing — and that really isn’t
all that surprising,” she said.
On the Net:
● New England Journal of Medicine: http://nejm.org
● federal dietary guidelines: http://www.health.gov/dietaryguidelines/dga2005/document/html/chapter2.htm
● Osteoporosis facts: http://www.osteo.org/newfile.asp?doc
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