A controversial new study has found high doses of vitamin E may
increase one's risk of dying. This represents a big change from
previous studies that showed vitamin E has either no effect on mortality
rates or lowered the mortality rate of cardiovascular disease.
Current U.S. dietary guidelines have set a high upper limit of
1,500 international units (IU) of vitamin E a day. Some adults in
the United States take doses of vitamin E (greater than 400 IU a
day), believing high doses will help them live longer.
In a study of 136,000 people in 19 trials,
researchers analyzed dosage levels and death rates. They found:
- The risk of dying within five years rose by about 5 percent
in people who took at least 400 IU a day (in 11 trials)
- The risk of death decreased by 1 percent in those who took
lower doses of vitamin E
Note: Because the results of this study do not reflect the population
at large, as high-dose trials were small and participants tended
to have chronic health problems, the cause of death cannot be attributed
solely to vitamin E intake.
Possible Causes Behind Vitamin E's Harmful
Effects
-
Vitamin E is an anti-coagulant, meaning it may increase the
risk of bleeding, which in turn contributes to stroke in those
taking blood-thinners
-
Taking irregular doses, resulting in withdrawal symptoms such
as chest pain when one's daily routine is interrupted
-
Vitamin E could become a free radical, damaging the proteins
and fats it typically protects
-
The type of vitamin E in supplements could take the place of
other antioxidants, harming the balance of antioxidant systems
New Scientist November 10, 2004
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