Breast Cancer Survivors Should Eat More Broccoli, Cabbage
Eating more broccoli, cabbage, and other cruciferous vegetables could improve your chances of survival if you are a woman with breast cancer. This dietary advice comes from the results of study presented at the American Association for Cancer Research (AACR) Annual Meeting 2012.
Cruciferous veggies are cancer fighters
Some people still turn up their noses at broccoli, kale, and other cruciferous vegetables, but the evidence concerning their health benefits, especially associated with cancer, has been growing steadily. This latest study is yet another example.
Sarah J. Nechuta, MPH, PhD, a postdoctoral research fellow at Vanderbilt University, and her team evaluated the effect of consuming cruciferous vegetables in a group of 4,886 Chinese breast cancer survivors who had been diagnosed with stage 1 to stage 4 disease from 2002 to 2006.
When the investigators looked at the women’s dietary habits and lifestyle factors, they discovered that those who ate cruciferous vegetables during the first three years after their breast cancer diagnosis experienced the following benefits based on the amount of vegetables they ate:
- Their risk for death from any cause decreased by 27% to 62%
- Their risk for death from breast cancer decreased by 22% to 62%
- Their risk for recurrence of breast cancer decreased by 21% to 35%
The more cruciferous vegetables the women ate, the better the benefit.
Wide variety of cruciferous vegetables
Broccoli and cauliflower may be the most recognized cruciferous vegetables in the United States and other Western countries, but there are many more options. In this study, the Chinese women tended to consume turnips, bok choy/Chinese cabbage, and greens.
Chinese women not only eat different cruciferous vegetables than do their Western counterparts, they also eat more of them. Nechuta explained the significance of these differences: “The level of bioactive compounds such as isothiocyanates and indoles, proposed to play a role in the anticancer effects of cruciferous vegetables, depend on both the amount and type of cruciferous vegetables consumed.”
In addition to the cruciferous vegetables already mentioned, others include arugula, broccoflower, broccoli rabe, Brussel sprouts, collard greens, daikon, horseradish, kale, kohlrabi, mustard greens, radishes, rutabaga, wasabi, and watercress.
Other research on cruciferous vegetables
Previous research has highlighted the cancer benefits of eating cruciferous vegetables. For example, a 2011 study from researchers at the Linus Pauling Institute at Oregon State University showed for the first time that sulforaphane, a type of isothiocyanate in broccoli and other cruciferous vegetables, can target and kill cancer cells without damaging healthy cells.
In a new study published in the Annals of Oncology, researchers evaluated more than 12,000 individuals with different types of cancer and compared them with more than 11,000 healthy controls. Consumption of cruciferous vegetables at least once a week compared with occasional or no intake was associated with a significantly reduced risk of cancer of the pharynx, esophagus, colorectum, breast, and kidney.
Benefiting from cruciferous vegetables
How you prepare broccoli appears to have an impact on the anti-cancer properties of the vegetable. Overcooking broccoli destroys myrosinase, an enzyme that is necessary for the formation of sulforaphane. So if you want to reap the benefits of broccoli, lightly steam it.
In fact, here is a simple recipe that combines cruciferous vegetables favored by the Chinese and by Western eaters in one dish.
- ½ cup each cubed turnips, kohlrabi
- ½ cup red onion, chopped
- 1 cup each broccoli florets, cauliflower florets, and Brussel sprouts (cut in halves)
- ½ lb bok choy, chopped
- 1 tablespoon cornstarch
- 2 teaspoons chopped fresh ginger root
- 2 tablespoons soy sauce
- ¼ -1/2 cup water
Combine cornstarch, ginger, and oil together and mix well with all the vegetables in a bowl. Heat a wok on high, add the water and soy sauce, and cook the vegetables for 2-3 minutes, depending on how tender you like them. The vegetables will vary in crispness. Serve over brown rice.
More studies of the effect of eating cruciferous vegetables on breast cancer and other cancers are needed, and Nechuta suggested those studies include measurements of isothiocyanates and other compounds and their influence on breast cancer. In the meantime, it can’t hurt to include more cabbage, broccoli, and other cruciferous vegetables in your diet, whether you’re a breast cancer survivor or not.
American Association for Cancer Research
Bosetti C et al. Cruciferous vegetables and cancer risk in a network of case-control studies. Annals of Oncology 2012 Feb 10
Clarke JD et al. Differential effects of sulforaphane on histone deacetylases, cell cycle arrest and apoptosis in normal prostate cells versus hyperplastic and cancerous prostate cells. Mol Nutr Food Res 2011 Jul; 55(7): 999-1009
Image: Wikimedia Commons