DASH Diet Reduces Heart Disease Risk in Breast Cancer Survivors
Following the DASH — Dietary Approaches to Stop Hypertension — diet reduced the risk of heart problems in women who had been treated for breast cancer, according to a study published in the journal NCI Cancer Spectrum.
Key takeaways
Women whose diets were most similar to the DASH diet when they were diagnosed with breast cancer had a lower risk of various heart problems, including heart failure, heart attack, irregular heartbeat, heart valve disease, and blood clots, than women whose diets were the least like DASH.
The DASH eating plan was designed to help treat or prevent high blood pressure. It recommends eating vegetables, fruits, and whole grains, as well as fat-free or low-fat dairy products, fish, poultry nuts, and vegetable oils, and limiting saturated fats, sugar-sweetened beverages, and sweets.
What the results mean for you
Breast cancer treatments can increase the risk of heart disease in some women. Certain breast cancer treatments can cause heart problems, especially the chemotherapy medicine Adriamycin (chemical name: doxorubicin) and other anthracyclines, and the targeted therapy Herceptin (chemical name: trastuzumab). And research has found that cancer survivors have a higher risk of developing heart disease than people with no history of cancer. Among women with a history of breast cancer, heart disease is the number one cause of death, excluding breast cancer.
This study suggests that diet may be one way to lower your risk of heart problems. The DASH diet is very similar to what many dietitians recommend eating for a healthy diet:
a variety of vegetables of all colors
fruits, especially whole fruits
whole grains
a variety of protein foods, including lean poultry, fish, beans and peas, and nuts and seeds
avoiding added sugar, saturated fat, and processed foods
Besides eating a healthy diet, most experts also recommend exercising every day, and doing a total of 150 to 300 minutes of moderate exercise or 75 to 150 minutes of vigorous exercise each week.
About the study
For the study, the researchers analyzed information from 3,415 women who were part of the Pathways Study, a study looking at the roles diet, exercise, supplements, and friendship play in breast cancer survivorship. All the women were diagnosed with invasive breast cancer between 2005 and 2013.
Among the women in the study:
the average age at diagnosis was 60
68.7% were white
72.4% were post-menopausal
more than 80% of the women were diagnosed with stage I or stage II breast cancer that was estrogen receptor-positive and HER2-negative
55.2% had had high blood pressure, diabetes, or high cholesterol before being diagnosed with breast cancer
6.8% had had a cardiac event before being diagnosed with breast cancer, including coronary artery disease, heart failure, cardiomyopathy (heart muscle disease), or stroke
About two months after they were diagnosed, the women filled out a food intake questionnaire that asked them about what they ate in the previous six months.
The researchers then analyzed the women’s diets to see how closely they followed the DASH diet and gave their diets a DASH score. The DASH score was calculated by how often the women ate seven types of foods and how much sodium their diet included. Beneficial foods were vegetables, fruits, nuts, grains, and low-fat dairy. Poor foods were red and processed meat and sugar-sweetened beverages, and more sodium also counted negatively. Scores range from 0 to 40.
The researchers compared the women’s DASH score to the cardiovascular events that happened from the time the women were diagnosed with breast cancer to December 31, 2021, about 11.5 years.
Detailed results
During follow-up, the women in the study had 650 cardiac events in total, and 341 women died from a cardiac event.
Compared to women whose didn’t follow the DASH diet, women whose diets were most closely aligned with the DASH diet had a:
47% lower risk of heart failure
23% lower risk of coronary artery disease
23% lower risk of heart attack
21% lower risk of heart valve disease
25% lower risk of blood clots
“Our findings suggest that we need to begin talking to breast cancer survivors about the potential heart benefits of the DASH diet,” the paper’s lead author, Isaac Ergas, PhD, staff scientist at the Kaiser Permanente Division of Research, said in a statement. “We know that breast cancer survivors have an elevated risk for cardiovascular disease, and the diet might be able to help improve the overall health of this population.”
Limitations
While the results of this study strongly suggest that the DASH diet can benefit women with a history of breast cancer, it’s important to know that the researchers got their information about the women’s diets by asking them to remember what they ate in the six months before they joined the study.
About two months after they were diagnosed with breast cancer, the women filled out a questionnaire asking how many times they ate certain foods in the previous six months about two months after they were diagnosed with breast cancer. Right after a diagnosis, many people feel overwhelmed, anxious, frightened, angry, or all of these emotions. If they’ve started treatment, especially chemotherapy, they may have problems with thinking and remembering things.
The results of this study are based on assuming that the women accurately reported what they ate. But sometimes people don’t remember everything they eat or how much of something they eat, especially several months ago. This would affect the results of the study.
Still, the DASH diet isn’t harmful, and following it can help you be as healthy as you can be. The results of this study echo results from earlier studies showing that a healthy lifestyle, including a healthy diet, may help women live longer after being diagnosed with breast cancer, and may also reduce the risk of recurrence (breast cancer coming back).
Learn more
Listen to a podcast episode featuring registered dietitian and oncology nutrition specialist Hillary Sachs discussing nutrition and breast cancer.
Ergas, I., et al. Diet quality and cardiovascular disease risk among breast cancer survivors in the Pathways Study, JNCI Cancer Spectrum, Volume 8, Issue 2, April 2024.
Updated on August 31, 2024