NEW YORK, Jul 21 (Reuters Health) - Taking a daily multivitamin in
combination with one of the antioxidant vitamins A, C or E appears to reduce the
risk of dying from heart disease and stroke, results of a study suggest.
However, this vitamin regimen may also increase the risk of dying from
cancer in male smokers, the authors report in the July issue of the American
Journal of Epidemiology.
The findings "warrant corroboration," write Margaret L. Watkins and
colleagues from the Centers for Disease Control and Prevention (CDC) in Atlanta,
Georgia. They call for further studies to examine the role that vitamins and
vitamin combinations may play in dying from heart disease, cancer and
stroke--the three leading causes of death in the US.
In the study, which included more than 1 million adults aged 30 and older,
researchers compared death rates of those who used multivitamins alone; vitamin
A, C or E alone; or a multivitamin with vitamin A, C or E; with death rates of
people who did not take vitamins, over a 7-year period.
The investigators found that adults who took a multivitamin with an
antioxidant vitamin had a 15% lower risk of dying from heart disease and stroke
than people who did not take vitamins. Risk appeared to fall with time as
individuals took the vitamin combination.
However, there was no survival advantage among people who took a
multivitamin alone. "One explanation is that there may be a minimum dose of a
single vitamin or combination of supplements necessary for risk reduction," the
researchers suggest.
In other findings, the risk of death from cancer was the same among vitamin
users and non-users. Use of multivitamins alone or with other vitamins seemed to
increase the risk of dying from all cancers, compared with using vitamin A, C or
E alone, the report indicates.
Male smokers who used multivitamins alone or in combination with other
vitamins had a higher risk of dying from cancer than nonsmoking males who took
vitamins. What's more, men who smoked and took vitamins had a higher risk of
dying from prostate cancer than male smokers who did not take vitamins.
These findings support previous research demonstrating that high doses of
beta-carotene can increase the risk of dying from lung cancer in male smokers.
The authors suggest that the use of vitamin A, C or E may counterbalance the
observed elevated cancer mortality risk among men who used multivitamins.
They also note that adults who took vitamins tended to be more educated and
less overweight than those who did not. Vitamin-takers were also more likely to
eat vegetables and drink wine or liquor.
