WASHINGTON (Reuters) - Mice fed plenty of flaxseed
seemed to be protected against the worst forms of prostate cancer, which suggests flaxseed contains some protective components, U.S.
researchers said on Monday.
Flaxseed is a rich source of omega-3 fatty acids,
fiber and compounds known as lignans, all of which may play a role in protecting
against cancer and perhaps also heart disease.
A team at Duke University Medical Center fed large
amounts of flaxseed to mice that were genetically engineered to develop prostate
cancer. They compared them to genetically engineered mice that were not fed any
flaxseed.
About 3 percent of the mice did not develop prostate
cancer at all and the rest had smaller tumors that were less likely to spread,
thy reported in the journal Urology.
"Tumors in the untreated control group were twice
the size of tumors in the flaxseed group," Dr. Xu Lin, who led the study, said
in a statement.
"The tumors were also less aggressive in the
flaxseed group, and two of the mice in the flaxseed group did not develop
prostate cancer at all."
Other research has suggested that men who eat
flaxseed have lower levels of prostate specific antigen, a protein produced by
prostate cells that is now used as a test for prostate cancer. The higher the
levels, the more likely it is that a man has prostate cancer.
"We are cautiously optimistic about these findings,"
urologist Wendy Demark-Wahnefried, who helped lead the study, said in a
statement.
"The amount of flaxseed given to each mouse was 5
percent of its total food intake, which would be a very difficult amount for
humans to eat, but it does signal that we are on the right track and need to
continue research in this area."
The team is now doing a study in men with prostate
cancer.
About 30,000 U.S. men die every year of prostate
cancer, the second biggest cancer killer of men after lung cancer.
