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Centrum Silver and other MVTs |
The
daily use of multivitamins may reduce the risk for cancer in men, according to
the results of a very large randomized trial in the US
A number of trials of individual vitamins, administered at high doses,
have not shown any effect at preventing cancer. Observational studies have also
not provided evidence of an association between multivitamin use and a reduction
in cancer incidence or mortality.
However, the current study is unique in a
number of ways, the first being that it is the only large-scale
placebo-controlled trial evaluating a multivitamin in the prevention of cancer.
It is also of long duration and involved
physicians themselves as the subject.
After
about 11 years, multivitamin use resulted in a modest but statistically
significant reduction — specifically, an 8% reduction in total cancer
incidence.
The study involved 14,641 male US
physicians initially aged ≥50 years (mean age, 64.3 years), including 1312 men with
a history of cancer at randomisation, enrolled in 1997 with treatment and
follow-up through to June 1, 2011. They received either daily exact same brand multivitamin
(Centrum Silver) or placebo. The main outcome measures were total cancer
(excluding non-melanoma skin cancer), with prostate, colorectal, and other
site-specific cancers among the secondary end points.
During a median follow-up of 11.2 years:
• There were 2669 men with confirmed
cancer, including 1373 cases of prostate cancer and 210 cases of colorectal cancer.
• Compared with placebo, men taking a daily
multivitamin had a statistically significant reduction in the incidence of
total cancer (multivitamin and placebo groups, 17.0 and 18.3 events,
respectively, per 1000 person-years; hazard ratio [HR], 0.92; 95% CI, 0.86 to
0.998; p=0.04).
• There was no significant effect of a
daily multivitamin on prostate cancer (multivitamin and placebo groups, 9.1 and
9.2 events, respectively, per 1000 person-years; 0.98; 0.88 to 1.09; p=0.76),
colorectal cancer (multivitamin and placebo groups, 1.2 and 1.4 events,
respectively, per 1000 person-years; 0.89; 0.68 to 1.17; p=0.39), or other
site-specific cancers.
• There was no significant difference in
the risk of cancer mortality (multivitamin and placebo groups, 4.9 and 5.6
events, respectively, per 1000 person-years; 0.88;, 0.77 to 1.01; p=0.07).
• Daily multivitamin use was associated
with a reduction in total cancer among 1312 men with a baseline history of
cancer (0.73; 0.56 to 0.96; p=0.02), but this did not differ significantly from
that among 13,329 men initially without cancer (0.94; 0.87 to 1.02; p=0.15; p
for interaction=0.07).
Reduction
in Total Cancers
"Our main message is that the main
reason to take a multivitamin is for nutritional deficiencies but it certainly
appears that there may be a modest benefit in preventing cancer in men over the
age of 50," lead author John Michael Gaziano said.
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The study has also been published online October
17, 2012 in the Journal of the American Medical Association Published:
Gaziano JM, Sesso HD, Christen WG, Bubes V,
Smith JP, MacFadyen J, Schvartz M, Manson JE, Glynn RJ, Buring JE. Multivitamins in the Prevention of Cancer
in MenThe Physicians' Health Study II Randomized Controlled Trial . JAMA. 2012;():1-10.
doi:10.1001/jama.2012.14641.
You can read the full text HERE