January 3, 2007 - According to the American Cancer Society, nearly 213,000 women will be diagnosed every year with invasive breast cancer in the United States. Nearly 41,000 women will die from the disease. The risk of a woman developing breast cancer in her lifetime is one in eight. The chance of dying from it is one in 33. Christine Ambrosone, Ph.D., from the Roswell Park Cancer Institute in Buffalo, N.Y., says, "We don't know very much about what causes breast cancer. Two things that we know are alcohol consumption increases the risk of breast cancer and physical activity decreases the risk of breast cancer." But what about diet?
BREAST CANCER AND NUTRITION: Ambrosone says, "When we think about what causes cancer and how DNA is damaged and what prevents DNA damage, some of the components in fruits and vegetables should play a very important role." Fruits and vegetables contain powerful antioxidants that reduce oxidative damage to cells and biomolecules. Studies on whether or not fruits and vegetables decrease the risk of breast cancer have been somewhat conflicting. One major study -- the Nurse's Health study -- showed no reduction in breast cancer risk among women who consumed higher amounts of fruits and veggies. (Note: there were subsets of types of vegetables that were associated with a reduced risk, including cruciferous vegetables such as broccoli, brussels sprouts and cauliflower). However, when women are separated into groups by genotype, the effects of fruits and veggies becomes much clearer.
IT'S YOUR GENES: Ambrosone's research shows the benefits of fruits and vegetables could largely depend on your genetic makeup. In three separate studies, she found a direct effect of fruits and veggies on breast cancer risk in relation to three different genotypes.
In the first study, Ambrosone found women who had a genotype called Manganese Superoxide Dismutase -- or MnSOD -- had an increased risk of breast cancer. When those women consumed high amounts of fruits and vegetables, the risk associated with that genotype was greatly reduced.
In a second study, Ambrosone studied women with a variant of the gene myeloperoxidase. This gene variant actually offers protection against breast cancer, but only among women who consumed a diet high in fruits and vegetables.
In her latest study, Ambrosone studied the catalase genotype. The catalase genotype is also protective against breast cancer. In the study, Ambrosone found women who had the most common genotype -- the CAT C (CC) -- had a 30-percent lower risk of breast cancer if they ate just 10 servings of fruits and vegetables a week. Among women with the same genotype who ate few fruits and vegetables, that risk reduction was only 5 percent. About 64 percent of the population has the CAT C (CC) genotype.
The genotypes Ambrosone studied are very common so her take-home message is simple. She advised women, "Don't worry about your genotype. Eat a healthy diet. There are so many other genes and genotypes that will play into these complex relationships that trying to sort out the role of all of them really does not make sense." Those few extra fruits and veggies could go a long way in giving some added protection against the most common cancer in women.
|
