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Studies reviewing lycopene and the
incidence of breast cancer Breast cancer is the most common cancer
and cause of death from cancer in women throughout the world. Most people
know that diets high in fruits and vegetables probably reduce the risk of
developing cancer, but now studies indicate that high consumption of tomatoes
and tomato products also reduces the risk of developing breast cancer. The
reason? Lycopene, an antioxidant that inhibits tumors and is more easily
absorbed by the body when tomatoes are processed into juice, sauce and paste.
There are three different sets of evidence
for the protective role of lycopene in breast cancer: a) cell culture
studies, b) animal studies, and c) epidemiological studies. In cell culture studies, lycopene's
activities in inhibiting breast cancer tumors were compared with those of
alpha and beta-carotene(1). The cell cultures that were enhanced with
lycopene showed that it inhibited the growth of breast cancer cells (MCF-7),
and that alpha and beta-carotene were far less effective than lycopene in
inhibiting the cell growth. When lycopene was fed to mice genetically
susceptible to developing breast tumors(2), it was found that lycopene-fed
mice had suppressed and delayed tumors. Another study(3) showed that rats
injected with lycopene developed fewer and smaller size carcinogen-induced
tumors than rats without lycopene injections. Beta-carotene didn't provide
any protection against breast tumors in this study. Several
studies have showed insignificant or no association between either lycopene
from the diet(4) and concentrated lycopene(5) and breast cancer risk, however
others have found a relationship between breast tissue lycopene and breast
cancer risk(6). A recent study of samples(7) taken from The Breast Cancer
Serum Bank in Columbia, Missouri were analyzed to evaluate the relationship
of levels of carotenoids (including lycopene), selenium and retinol with
breast cancer. Only lycopene was found to reduce the risk for developing
breast cancer. Other carotenoids were not found to be associated with reduced
breast cancer risk, however long-term studies are needed to establish the
protective role of lycopene in breast cancer. References
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