Your mom was always right - we should be eating all of those fruits and vegetables. A recent comprehensive review of research from the American Institute for Cancer Research (AICR) found eating low-fat foods, and increasing fruits and vegetables, does in fact decrease the risk of breast cancer. What veggies and fruit you eat, and how they are prepared, matters too!
The recent AICR study asked people about their eating habits and then followed them to see if health problems could be linked back to their dietary practices. The people who ate the most fruits and vegetables had an 11 percent reduction in risk of breast cancer. Additionally, the highest fruit consumption linked with a six percent reduction in risk and highest vegetable consumption was about a one percent reduction in risk (which is too small to be statistically significant).
When analyzing the amount of fruit and vegetable intake, it was found that each 1 to 2 cup intake of fruits and vegetables accounted for about a four percent decrease in risk. So the amount matters: the more you eat, the lower your risk. Another factor is what kinds of fruits and vegetable people eat. Try to choose produce that is rich in color; It usually means the fruit or veggies has the highest antioxidant content.
Dark leafy greens
The AICR also reviewed multiple studies looking at carotenoids, veggies and fruits with deep orange, red and greens. Carotenoids are powerful antioxidants that are linked to preventing some forms of cancer and heart disease, and act to enhance your immune response to infections. The results showed that the highest consumption of beta-carotene is linked to a seven percent reduction in risk of breast cancer, but no benefit was seen from beta-carotene supplements. But consumption doesn't always mean you get the highest quantities of the nutrients. Absorption of nutrients is increased when these vegetables are cooked and consumed with a modest amount of fat. So for the people cooking their veggies optimally, the highest blood levels of total carotenoids was linked with a 26 percent decrease in breast cancer risk.
Did you eat your Brussel sprouts?
Cruciferous vegetables, like cabbage, broccoli and collard greens, have also been long-touted for their role in breast cancer prevention. Some of these vegetables, such as Brussel sprouts and kale, are also rich in carotenoids, which may account for some of its cancer-fighting power, but those particular vegetables also contain indole-3-carbinol. This compound has been found in laboratory studies to inhibit enzymes that activate carcinogens, turn on expression of tumor suppressor genes and shift estrogen metabolism to a weaker, less cancer-promoting form. Thirteen population studies were done, which showed the highest consumption of cruciferous vegetable is associated with a 15 percent decreased risk of breast cancer. Again, amount matters. In Chinese populations, the highest consumption was linked to 22 percent reduced risk, but the highest consumers in China ate considerably more than the highest consumers in the U.S. and Europe.
Here's an interesting fact about cruciferous vegetables - they are less likely to be eaten by people who can taste PTC, an organic compound. PTC has the unusual property that it either tastes very bitter or is virtually tasteless, depending on your genetic makeup.
The bottom line is the best-known prevention of breast cancer is to obtain or maintain a healthy weight, since there is convincing evidence of increased risk with overweight and adult weight gain. That means exercise regularly, eat a low-fat diet and limit alcohol intake (1 drink per day for women, reduced to no more than three per week if you have a family history of breast cancer). Along with helping you maintain a healthy lifestyle, adding more fruits and vegetables to your diet can help prevent breast cancer.
To learn more about "Nutrition for Breast Cancer Prevention," join me tonight from 5:30 to 7 p.m. at Jack's Place in Edwards as I talk about fruits and veggies and other nutrition strategies for prevention. This program is free and open to the public. A light "prevention dinner" will be served. For more information on Shaw Regional Cancer Center, visit www.shawcancercenter.com.
Mel Hendershott is a registered dietitian and oncology nutritionist at Shaw Regional Cancer Center. Email comments about this story to firstname.lastname@example.org.