For the past seven years lycopene
has played the role of Superman on the Shelves of health food stores.
Since a 1996 Harvard University study found that men who ate at least
10 weekly servings of tomato sauce were a third less likely to develop
prostate cancer, the powerful antioxidant abundant in tomatoes has
been in the public and scientific spotlight.
Now according to another study, lycopene has no anti-cancer effect
when taken in a pure form as a nutritional supplement.
The study, conducted by researchers at the University of Illinois,
Urbana, and Ohio State University, Columbus, found that lycopene alone
did virtually nothing to protect laboratory rats against prostate
cancer while consumption of tomatoes reduced prostate cancer deaths
by nearly 20 %.
In a study published Nov. 5 in the Journal of the National Cancer
Institute, researchers said a combination of nutrients in tomatoes,
including lycopene, protect against prostate cancer.
Steve Clinton, a professor of hematology, oncology and human nutirtion
at Ohio State and the lead author of the study, said tomatoes contain
hundreds of phytochemicals that, when combined, possibly help protect
against prostate cancer.
“Our study does not say lycopene is useless,” Clinton
said. “Instead it suggests if we want the health benefits of
tomatoes, we should eat tomatoes or tomato products and not rely on
lycopene supplements alone.”
Peter Gann, associate professor of preventive medicine at Northwestern
University, Evanston, Ill., who was not involved in the study, said
the findings are important and helps to answer a nagging question
regarding natural healthful compounds. Which is best? Taking a single
nutrient in pill form or eating the whole food?
“This study gives us new evidence that eating a whole food might
bring health benefits that we cannot get from taking pills that isolate
one or two food ingredients,” Gann said. “Fortunately
in this case, the food in question is already popular.”
According to the U.S Department of Agriculture, Americans consume
an average of 92 pounds of tomato products per year, mostly in salads,
pasta, pizza sauce, chili and salsa.
Clinton’s research team gave three groups of rats a chemical
that causes prostate cancer.
In a 14-month period, one group got standard rat food, another got
rat food laced with lycopene, and a third group got rat food with
a tomato powder that contained lycopene and other pytochemicals.
The research found that rats in the first two groups died at a rate
of 80% and 72%, respectively. The fatality rate among the rats fed
tomato powder was 62%.
“Tomato powder consumption clearly extended the life and reduced
the cancer in this model,” said John Erdman Jr., a professor
of food science and human nutrition at Illinois. “Lycopene was
a little better than the contol group but not as good as the tomato
powder group.”
Erdman and Clinton say more work is necessary to discover the role
of phytochemicls in tomatoes and to determine if there are positive
effects among the compounds.
“Our findings strongly suggest that risks of poor dietary habits
cannot be reversed by taking a pill,” Clinton said. “We
shouldn’t expect easy solutions to complex problems. We must
focus more on choosing a variety of healthy foods, exercising and
watching our weight.
The research was supported by the U.S. Public Health Service, National
Cancer Institute, National Insitutes of Health and the U.S. Department
of Health and Heman Services.
