From the ArcaMax Publishing, Health & Fitness Newsletter:
http://www.arcamax.com/news/healthtips/s-572022-109424
BOSTON (UPI) -- Higher selenium levels in the blood may worsen
prostate cancer in some men who have the disease, U.S. researchers
said.
Researchers at Dana-Farber Cancer Institute in Boston and the
University of California, San Francisco, said a higher risk of
more-aggressive prostate cancer was seen in men with a certain genetic
variant found in about 75 percent of the prostate cancer patients in
the study.
In those subjects, having a high level of selenium in the blood was
associated with a two-fold greater risk of poorer outcomes than among
men with the lowest amounts of selenium.
In contrast, the 25 percent of men with a different variant of the
same gene and who had high selenium levels were at 40 percent lower
risk of aggressive disease.
The variants are slightly different forms of a gene that instructs
cells to make manganese superoxide dismutase, an enzyme that protects
the body against harmful oxygen compounds, the researchers said.
The findings suggest that "if you already have prostate cancer, it may
be a bad thing to take selenium," senior author Dr. Philip Kantoff,
director of Dana-Farber's Lank Center for Genitourinary Oncology, said
in a statement.
Supplements of selenium have been sold and promoted as a means of
preventing prostate cancer -- largely based on observational studies
that found higher risk of prostate cancer incidence and mortality in
areas of the country that are naturally low in selenium, Kantoff said.
The findings are published online ahead of print in the Journal of
Clinical Oncology.