Cruciferous Vegetables Are Linked to Lower Breast Cancer Risk
Cruciferous vegetables are a rich, natural source of vitamins, fiber, and antioxidants. Cancer researchers suggest they even help in protecting against a variety of cancers — including breast, prostate, and colon cancer.
Additionally, these super-vegetables are noted for reducing chronic inflammation, preventing diabetes, and slowing down aging, as revealed in a number of scientific studies.
Cruciferous vegetables and their link to lowering breast cancer risk
Cancer researchers found a link between cruciferous vegetables and protection against breast, prostate, colorectal, and lung cancers.
A study performed by a team of researchers at Vanderbilt Ingram Cancer Center and Shanghai Center for Disease Control and Prevention revealed that breast cancer survivors who eat more cruciferous vegetables may have improved survival.
The researchers investigated the role of cruciferous vegetables in breast cancer survival among women in the Shanghai Breast Cancer Survival Study. From 2002 to 2006, the group of researchers performed a prospective study of 4,886 Chinese breast cancer survivors who were diagnosed with stage 1 to stage 4 breast cancers.
After the researchers adjusted the study for lifestyle factors, clinical characteristics, and demographics, they found “cruciferous vegetable intake during the first 36 months after breast cancer diagnosis was associated with a reduced risk for total mortality, breast cancer-specific mortality and disease recurrence.”
The researchers noted survival rates were influenced by vegetable consumption in a dose-response pattern. As women consumed more of these vegetables, their risk of cancer recurrence or death decreased.
The findings also showed that breast cancer survivors who ate more cruciferous vegetables during the three years after the diagnosis reduced their risk of dying 27 to 62 percent compared to women who reported no consumption of these vegetables.
Cruciferous vegetable consumption habits differ between China and the United States. This factor should be considered when simplifying these results to U.S. breast cancer survivors.
Sarah J. Nechuta, Ph.D., M.P.H., Assistant Professor at the Vanderbilt University School of Medicine, Division of Epidemiology, and Department of Medicine, Nashville, Tennessee noted, “Commonly consumed cruciferous vegetables in China include turnips, Chinese cabbage/bok choy and greens, while broccoli and Brussels sprouts are the more commonly consumed cruciferous vegetables in the United States and other Western countries. The amount of intake among Chinese women is also much higher than that of U.S. women.”
Biological compounds that help to prevent cancer
The National Cancer Institute reports cruciferous vegetables are rich in nutrients, including several carotenoids, such as beta-carotene, lutein, and zeaxanthin. They are a rich source of vitamins C, E, and K, as well as folate and a variety of minerals.
Cruciferous vegetables contain a group of substances known as glucosinolates — which are sulfur-containing chemicals. These chemicals are responsible for the bitter flavor and pungent aroma of the vegetables.
In addition, the National Cancer Institute notes that all through “food preparation, chewing, and digestion, the glucosinolates in cruciferous vegetables are broken down to form biologically active compounds such as indoles, nitriles, thiocyanates, and isothiocyanates. Indole-3-carbinol (an indole) and sulforaphane (an isothiocyanate) have been most frequently examined for their anticancer effects.”
Indoles and isothiocyanates are found to hinder the development of cancer in several organs in rats and mice, including the breast, colon, lung, liver, stomach, and bladder. Studies in animals and experiments with cells grown in laboratories have identified several possible ways these compounds may help in preventing cancer:
- They induce cell death (apoptosis).
- They have antiviral and antibacterial effects.
- They inhibit tumor blood vessel formation (angiogenesis) and tumor cell migration (needed for metastasis).
- They have anti-inflammatory effects.
- They help inactivate carcinogens.
- They help protect cells from DNA damage.
More about these super-vegetables
Cruciferous vegetables contain large amounts of fiber — essential for a healthy digestive system. Dietary fibers help in the prevention of diabetes, reduce cholesterol, improve the digestive system, and prevent colon cancer.
Part of the family of Brassica genus of plants, these super-vegetables include the following:
- Brussels sprouts
- Collard greens
- Bok choy
An article published in the Journal of the Academy of Nutrition and Dietetics noted that in animal studies, higher consumption of cruciferous vegetables — or certain key compounds within them — has been found to lower inflammation.
The researchers of this study wanted to see whether that is the case in people, as well. Senior author of the Vanderbilt University Medical Center study, Dr. Gong Yang told Reuters Health by email that his colleagues analyzed signs of inflammation in the blood of 1,005 middle-aged Chinese women who filled out questionnaires about their diets as part of the Shanghai Women’s Health Study.
The results of the study showed more than 1,000 Chinese women who ate the most cruciferous vegetables had substantially less inflammation than those who ate a fewer amount.
Dr. Yang notes, “Cruciferous vegetables may have health benefits through modulating inflammation. However, it is premature to make any dietary recommendation on the basis of this single observational study.” He added, “Bottom line, if you’re eating a lot of cruciferous vegetables your health is better, and specifically, inflammation markers are diminished. That means you’re going to have a healthier heart and you’re going to live longer.”
Rather than eating cruciferous vegetables raw, it’s better to cook them — making them easier to chew and more digestible. Eating raw carrots and celery is certainly fine; however, it’s far better to cook cauliflower and broccoli.
In addition, eat more than one serving of these super-vegetables each day. Use a variety of combinations based on their color. For example, mix the color of vegetable servings to include cauliflower and carrots, or broccoli and carrots. You might try Brussels sprouts and sweet potato, as well.
Additionally, try not to overcook cruciferous vegetables. When they’re overcooked, they may produce a sulfur odor and may not be appeal to your taste.
Remember, what you eat is just an additional way of preventing diseases. Cruciferous vegetables contain a variety of rich, natural disease-fighting nutrients to help you feel better and improve your health.