| Dietary
Supplement Commonly Used To Help Prevent Osteoporosis May Also Be
Protecting Women Against Heart Disease
Just when millions of women -- and their doctors -- are
questioning the efficacy of hormone replacement therapy in
reducing the risk of heart disease, a new study suggests that
commonly used dietary supplements may actually be providing some
of the protection they seek. According to a report from New
Zealand researchers in the April issue of the American Journal of
Medicine, taking calcium citrate may protect postmenopausal women
not only from bone fractures but also from heart disease. The
findings of Dr. Ian Reid and colleagues from the Department of
Medicine at the University of Auckland are from a one year
supplementation study with 223 postmenopausal women who had not
regularly used estrogens in the year prior to starting the study.
Dr. Reid told the Dietary Supplement Information Bureau:
"Our study illuminates a possibly overlooked effect of
calcium supplementation: improvement of blood cholesterol
profiles. With many postmenopausal women already taking calcium
supplements and living with a higher risk of heart disease, the
public health benefits may extend beyond simply reducing bone
fracture risk," said Reid. "A supplement as inexpensive
as calcium citrate, with multiple health protective effects, could
have major public health implications."
The women were all at least 55 years of age and had been
postmenopausal for at least five years. The average age in the
study group was 72.
Reid told the DSIB that women in the trial were consuming 910
mg of dietary calcium on average at the beginning of the study.
They were then assigned to take 1,000 mg of calcium (as calcium
citrate), or a placebo, as two 200 mg tablets before breakfast and
then three 200 mg tablets in the evening. Blood cholesterol
profiles were measured at the beginning of the study, and after 2,
6, and 12 months of supplementation.
"By the end of a year, the women supplementing with
calcium citrate showed a significant 7% increase in HDL. This
magnitude of increase parallels that seen with statin drugs, and
is associated with a 20-30% reduction in cardiovascular events.
LDL cholesterol dropped by 6 % in the same women.
No appreciable changes appeared in the women receiving the
placebo, for either type of cholesterol," added Reid.
"Our study is the longest and largest calcium-lipids clinical
trial to date, leaving us with many questions. Is calcium citrate
better than other forms? How would men or younger postmenopausal
women respond? And, most importantly, does supplementation with
calcium citrate reduce cardiovascular events and deaths?"
"These findings are indeed provocative," said David
Heber, M.D., director of the UCLA Center for Human Nutrition and a
member of the DSIB Scientific Advisory Board. "Could women
who are currently using calcium citrate to reduce the risk of
osteoporosis-associated fractures unknowingly be reducing their
risk of heart disease, too? While the women in this study started
off with already high, cardioprotective amounts of HDL cholesterol
in their blood, the findings of Dr. Reid and his colleagues could
widen the scope of future calcium supplementation studies. We also
need to address the genetic underpinnings of this study. We need
to ask whether New Zealand women typify the response of North
American, Asian, and European women, for example."
The study was sponsored by the Health Research Council of New
Zealand.
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