Kelly Jamieson Thomas
Every October we don our pink ribbons and draw awareness to breast cancer. This tradition is a wonderful way to bring us together to discuss how we may move forward in our fight against breast cancer. In the United States, breast cancer is the second most commonly diagnosed cancer in women and the second leading cause of cancer death in women. During their lifetime, 1 in 8 women will develop invasive breast cancer—a startling statistic for any woman to face. Of those diagnosed, only 5-10% carry genetic mutations in BRCA genes and less than 15% have family members with breast cancer, which indicates that most breast cancer cases are not hereditary. This gives us hope that we can lower breast cancer risk through prevention. In honor of breast cancer awareness month, let’s focus on how we can optimize prevention in addition to how we can develop a cure.
What can we do to lower the percentage of women who will be diagnosed with breast cancer below 12%? We can change our diet to include particular foods that may aid our bodies in preventing cancer, thereby lowering our risk. Although research on this has had conflicting results, there are many studies that demonstrate that diet affects cancer risk. When patients are treated with chemotherapy, tamoxifen, herceptin, and etcetera the results aren’t always a “cured” patient, but we still treat patients with the therapies we have available. In light of this, shouldn’t we pay more heed to the studies demonstrating that consuming certain foods may also help us prevent disease onset? Two changes we can make to lower our risk of breast cancer are increasing our dietary fiber intake and eating more cruciferous vegetables.
High Fiber Intake and Breast Cancer
Several pieces of epidemiologic and scientific research support the link between higher fiber intake and lower breast cancer risk. A meta-analysis that analyzed the results of over 15 studies examining the role of dietary fiber in breast cancer prevention, published in Annals of Oncology, found that the greatest reduction in risk (approximately 25%) was observed when women consumed over 25 grams of soluble fiber per day. Studies have shown that modified citrus pectin (a soluble fiber) reduced tumor growth, angiogenesis, and metastasis in mice. A diet high in fiber reduced mammary tumor incidence in rat models. Epidemiologic studies have found lower levels of circulating estrogen and androstenedione (a precursor to estrogen) associated with high fiber intake. The anti-cancer protection fiber effects may be the result of fiber binding estrogen in the bowels, resulting in the removal of some estrogen, thereby preventing it from affecting the cells in breast tissue. High intake of dietary fiber also reduces the risk of becoming overweight/obese, which is a well-established risk for postmenopausal breast cancer. For me, this evidence is a great reason to add soluble fiber to my meals.
How can we up our soluble fiber intake?
For breakfast, try a bowl of oatmeal topped with strawberries, blueberries, and flax seeds. For snack, enjoy an apple, orange, or pear. For dinner, add some kidney beans or lentils to your meal. The average American consumes 15 grams of fiber per day. To reach 25+ grams, and potentially decrease your risk up to 25%, just add 1/2 cup of beans or two apples each day.
Cruciferous Vegetables and Breast Cancer
Cruciferous vegetables are another source of food that can offer us protection from cancer. Cruciferous vegetables are packed with carotenoids, powerful antioxidants that help reduce inflammation caused by free radicals. Cruciferous vegetables are also abundant in glucosinolates, sulfur-containing chemicals that are broken down during digestion, forming biologically active compounds (indoles, nitriles, thiocyanates, isothiocyanates) that act as chemo protective agents. Indole-3-carbinol (an indole) and sulforaphane (an isothiocyanate), two of active compounds formed when cruciferous vegetables are digested, have both been shown to inhibit cancer growth in mice and rates and induce apoptosis, programmed cell death, in human tumor cells. Indoles and isothiocyanates may offer anti-cancer protection by causing an increase in the levels of BRCA1 and BRCA2 proteins aid in repairing damaged DNA, a decrease in inflammatory molecules, and an increase in detoxification enzymes that protect DNA against damage from carcinogens and free radicals. A meta-analysis, published in Breast, of 13 epidemiologic studies indicated that high cruciferous vegetable consumption was associated with a 15% decrease in breast cancer risk. A study of European women who ate only one serving per week of cruciferous vegetables indicated that their breast cancer risk decreased up to 17%.
How can we add these extraordinary vegetables to our daily life?
Make a delicious salad with arugula, watercress, and kale. Snack on lightly steamed broccoli, Brussels sprouts, and cauliflower for an added dose of glucosinolates.
[quote]Let’s focus on how we can optimize prevention in addition to how we can develop a cure.[/quote]
The concept that changes in our diet can lower our cancer risk is not a new one. We know it’s possible to lower our risk by making conscious decisions about the foods we eat—the fuel for our cells to run properly through the course of our long lives. If we make small changes now, only two of which include increasing our fiber and cruciferous vegetable intake, we can help prevent cancer. Let’s draw awareness to breast cancer prevention and lower our risk through changes in the way we eat.