October is Breast Cancer Awareness Month
October is Breast Cancer Awareness Month. It began in 1985 as a collaboration between the American Cancer Society and the pharmaceutical division of Imperial Chemical Industries that discovered the cancer drug, tamoxifen. The original goal of Breast Cancer Awareness Month was to educate women about breast cancer and to promote the importance of getting a mammogram as a tool for early detection. The pink ribbon, widely recognized as a reminder of breast cancer, was co-created in 1992 by Estée Lauder and the editor-in-chief of Self Magazine, Alexandra Penny.
We know no cancer is 100% preventable. Women born today have a 12.9% or 1 in 8 chance of being diagnosed with breast cancer in her lifetime.[i] The National Cancer Institute has an online breast cancer risk assessment tool that can be used to help estimate the risk of a woman developing breast cancer in their lifetime. Recent expert reports estimate that successful lifestyle changes could prevent 25% to 30% of cases of breast cancer.[ii]
When asked, “What steps, if any, can women take to lower their chances of developing breast cancer?” 28% of the respondents said diet, according to a July 2024 Physicians Committee of Responsible Medicine/Morning Consult poll of 2,107 women. Vegetables were mentioned by 23% of the women, fruits were mentioned by 16% of the women, 17% were aware soy can reduce breast cancer risk, and 16% responded incorrectly that soy can increase the risk of breast cancer. These statistics have not changed much over the years. Sadly, 72% of the respondents said they have never received information or education on the link between diet and breast cancer the from their health care provider.
Breast Cancer Awareness Month has expanded beyond its early years of educating the public about symptoms and early detection to include educating the public on prevention and raising funds for cancer research. It is also a time to celebrate and support survivors and honor those lost to breast cancer.
There are several activities that you can participate during Breast Cancer Awareness Month. Check the websites of the organizations below to find an activity in the area where you live.
The Susan G. Komen Foundation (www.komen.org) has Race for the Cure and other walks and events during October to raise funds for awareness and research. Participating in these actives is one way people can get involved and show support and help raise money for the cause.
The American Cancer Society (www.cancer.org) conducts “Relay for Life” events throughout the year. Teams take turns walking/running over a 24-hour period. The relay raises cancer awareness, celebrates survivorship, honors and remembers loved ones, and raises funds for the organization.
“Let’s Beat Cancer,” created by the Physicians Committee for Responsible Medicine (www.pcrm.org) and breast cancer surgeon Dr. Kristi Funk (www.pinklotus.com), is holding rallies during September and October throughout the country. The “Let’s Beat Cancer” campaign, however, is ongoing. Their focus is on prevention and reducing the risk of recurrence. Their four-prong approach to minimize the risk of breast cancer that may also help after diagnosis is as follows:
1. Choose Plant-Based Foods. Plants help in weight loss. In addition, they are low in fat and high fiber which reduces estrogen levels, lowering the risk of breast cancer.
2. Move More. Exercise reduces the risk of breast cancer in post-menopausal women. Exercise also reduces the amount of circulating estrogen. Vigorous exercise such as fast bicycling or running can help in weight loss and boost the immune system.
3. Limit Alcohol. The Nurses’ Health Study and Health Professional Follow-Up Study of 88,084 women found women having one alcoholic drink per day increased their risk of alcohol related cancers (mostly breast cancer) by 13% compared to those who did not drink alcohol.[iii]
4. Maintain a Healthy Weight. Being overweight increases the risk of breast cancer after menopause (80% of breast cancer in the US occurs in women over 50 years of age). Fats tissue produces excess amounts of estrogen which increases the risk of breast cancer.
Choosing plant-based foods does help with weight loss not only because they are low in fat and high in fiber, but many are also loaded with nutrients that have cancer-prevention properties.
Another good organization is the American Institute of Cancer Research (www.aicr.org). They recognize many cancers are preventable and fund research and develop programs that mainly focus on cancer prevention. Although not 100% vegan, it does have a very strong plant-slant presence and may be more approachable for those who have not transitioned to a WFPB diet.
In researching foods that fight cancer, and breast cancer in particular, I found several studies that concluded the data is conflicting. I chose to share the data from an analysis of two large studies, Nurses’ Health Study and Nurses’ Health Study II that was published in the American Association of Cancer Research.[iv] The two studies involved 8,927 women with stage I-III breast cancer.
The consumption of fruits and vegetables in this analysis fell into two categories – 1) their effect on overall health and all-cause mortality and 2) their effect on breast cancer specifically. Below are some of their findings:
- Two servings of blueberries a week was associated with a 25% lower breast cancer-specific mortality and 17% lower all-cause mortality.
- A lower breast cancer-specific mortality was associated with strawberries as well as with mixed vegetables.
- Berries have bioactives that are anti-inflammatory, anti-proliferative, and anti-inflammatory. They inhibit cancer progression and stop the supply of blood vessels to cancer cells, thus inducing breast cancer cell death. Berries reduce growth and spreading of cancer cells to other parts of the body.
- Fruit juice consumption was associated with higher breast cancer and all-cause mortality, apple juice particular. No risk, however, was found drinking orange juice.
- Beta carotene’s antioxidant properties and its ability to inhibit cell growth is associated with a lower rate of breast cancer when eaten in higher amounts, especially tumors with negative ER status. (Excellent sources of beta-carotene include sweet potatoes, carrots, collard greens spinach, winter squash, and kale).
- High vegetable intake, particularly green leafy and cruciferous vegetables, were associated with better overall survival among breast cancer patients and a lower all-cause mortality risk in this study. However, other studies cited in this analysis found fruit or vegetable consumption was not significantly associated with overall mortality in patients with breast cancer, so there are conflicting findings.
- This study found higher-all cause mortality with the high intake of peas. It may possibly be due the peas having a higher glycemic index than other vegetables.
- Comparing eating fruits and vegetables with breast-cancer specific mortality with all-cause mortality, a significant inverse effect was noted, especially with ER negative tumors.
- The findings of the authors of the analysis of these two studies suggest “higher vegetable consumption, particularly green leafy and cruciferous vegetables was associated with better overall survival among patients with breast cancer.”
Other findings in this report that were not breast cancer specific but were lower in all-cause mortality include eating green leafy vegetables, cruciferous vegetables, fruits and vegetables high in Vitamin C, broccoli, vegetables high in beta carotene, and lettuce.
Various other studies have shown:
- Soy isoflavones regulate estrogen in the body. When there is too much estrogen, isoflavones will block estrogen receptors, lowering estrogen and suppress cancer occurrence. One particular isoflavone, genistein, reduces cell proliferation and promotes the division of normal cells. It also induces cancer cell death of ER+ cancers including breast cancer. Genistein is the most potent isoflavone for cancer prevention.[v]
- Pomegranates have the bioactive ellagitannin that can inhibit proliferation of various types of cancer cells including those of breast cancer.[vi]
- Green tea contains EGCG that strengthens immunity and prevents the onset, growth, and progression of breast cancer. [vii]
- Fiber is known to bind to circulating concentrations of estrogens and are then excreted.[viii]
- Matcha tea inhibits the reproduction of breast cancer stem cells.[ix]
- A study published in the Journal of Food Chemistry found cauliflower, Brussels sprouts, green onion, leek, and garlic “abolished” breast cancer growth. Orange bell pepper, English cucumber, radicchio, jalapeño pepper, potato, and beets nearly halved breast cancer cell growth. Eggplant, bok choy, carrot, tomato, endive, fennel bulb, and Romaine lettuce had no effect on breast cancer cell growth.[x]
- Cruciferous vegetables also known as brassicas include cabbage, bok choy, cabbage, watercress, Brussels sprouts, broccoli, arugula, kale, collard greens, radishes, and turnips. A meta-analysis of 13 studies conclude high consumption of cruciferous vegetables was “significantly associated with a reduced breast cancer risk.”[xi]
In conclusion, there are so many factors to consider when studying the effects of nutrition on cancer including how the study was designed, errors in participants’ self-reporting food diary, conflicts of interest by the authors, genetics of the participants, type and stage of cancer, number of participants, length of the study, and more. Outcomes can be conflicting and confusing. Overall keep in mind processed and red meats, sugars, alcohol and tobacco use, and overweight all increase cancer risk. The WFPB way of eating has numerous cancer-fighting phytonutrients as well as activates our health defense systems including our gut microbiome, DNA, our immune system, and the ability to grow or halt the formation of blood vessels. All have an influence in reducing cancer risk.
[i] Howlader N, Noone AM, Krapcho M, et al. (eds). SEER Cancer Statistics Review, 1975–2017, National Cancer Institute. Bethesda, MD, https://seer.cancer.gov/csr/1975_2017/
[ii] Harvie M, Howell A, Evans DG. Can diet and lifestyle prevent breast cancer: what is the evidence? Am Soc Clin Oncol Educ Book. 2015:e66-73. doi: 10.14694/EdBook_AM.2015.35.e66. PMID: 25993238.
[iii] Cao Y, Willett WC, Rimm EB, Stampfer MJ, Giovannuci EL. Light to moderate intake of alcohol, drinking patterns, and risk of cancer: results from two prospective US cohort studies. BMJ. 2015;351:h4238. Scoccianti C, Lauby-Secretan B, Bello PY, Chajes V, Romieu I. Female breast cancer and alcohol consumption: a review of the literature. Am J Prev Med. 2014;46:S16-S25.
[iv] Farvid, M., Holmes, M, Chen, W., Rosner, B., Tamimi, R., Willett, w., Eliassen, A. (Postdiagnostic Fruit and Vegetable Consumption and Breast Cancer Survival: Prospective Analyses in the Nurses’ Health Studies.Cancer Research (2020) 80 (22): 5134–5143. https://doi.org/10.1158/0008-5472.CAN-18-3515
[v] [v] Kim IS. Current Perspectives on the Beneficial Effects of Soybean Isoflavones and Their Metabolites for Humans. Antioxidants (Basel). 2021 Jun 30;10(7):1064. doi: 10.3390/antiox10071064. PMID: 34209224; PMCID: PMC8301030.
[vi] Adams LS, Zhang Y, Seeram NP, Heber D, Chen S. Pomegranate ellagitannin-derived compounds exhibit antiproliferative and antiaromatase activity in breast cancer cells in vitro. Cancer Prev Res (Phila). 2010 Jan;3(1):108-13. doi: 10.1158/1940-6207.CAPR-08-0225. PMID: 20051378; PMCID: PMC2805471.
[vii] Marín V, Burgos V, Pérez R, Maria DA, Pardi P, Paz C. The Potential Role of Epigallocatechin-3-Gallate (EGCG) in Breast Cancer Treatment. International Journal of Molecular Sciences. 2023; 24(13):10737. https://doi.org/10.3390/ijms241310737.
[viii] Farvid MS, Barnett JB, Spence ND. Fruit and vegetable consumption and incident breast cancer: a systematic review and meta-analysis of prospective studies. Br J Cancer. 2021 Jul;125(2):284-298. doi: 10.1038/s41416-021-01373-2. Epub 2021 May 18. PMID: 34006925; PMCID: PMC8292326.
[ix] Bonuccelli G, Sotgia F, Lisanti MP. Matcha green tea (MGT) inhibits the propagation of cancer stem cells (CSCs), by targeting mitochondrial metabolism, glycolysis and multiple cell signalling pathways. Aging (Albany NY). 2018 Aug 23;10(8):1867-1883. doi: 10.18632/aging.101483. PMID: 30153655; PMCID: PMC6128439.
[x] Boivin, D, Lamy, S, Lord-Dufour S, et al. Antiproliferative and antioxidant activities of common vegetables: a comparative study. Food Chem 2009;112:374-80.
[xi] Liu X, Lv K. Cruciferous vegetables intake is inversely associated with risk of breast cancer: a meta-analysis. Breast. 2013 Jun;22(3):309-13. doi: 10.1016/j.breast.2012.07.013. Epub 2012 Aug 9. PMID: 22877795.
