Survivors who have had a particular type of breast cancer are more at risk for weight gain than individuals without cancer, according to a recent study.

The study looked at patients with a family history of estrogen receptor (ER) negative invasive breast cancer. This classification designates breast cancer that does not need the hormone estrogen to grow (estrogen receptor negative) and has spread beyond the original location to other parts of the breasts or other parts of the body (invasive). All individuals who survived this type of breast cancer gained more weight than individuals who were cancer-free, and patients diagnosed in the past five years were found to be at the greatest risk for weight gain.

The research was supported by the Breast Cancer Research Foundation and the National Institutes of Health, and appeared in Cancer Epidemiology, Biomarkers & Prevention, the journal of the American Association for Cancer Research.

The study also found that statin use also impacted weight gain, with chemotherapy-treated breast cancer survivors who took statins putting on more weight than their chemotherapy-treated counterparts who had never taken statins.

One reason why the women on statins gained more weight could be that they tended to have a less healthy lifestyle and already be overweight, says Stephanie Bernik, MD, chief of surgical oncology at Lenox Hill Hospital in New York City.

“Women who take statins may have high cholesterol and high triglycerides,” she says. “They’re usually overweight and not leading a healthy lifestyle. When you are not feeling well, you tend to become more sedentary, and you may be eating poorly, which can lead to weight gain.”

While weight gain isn't a direct effect of chemotherapy, using steroids along with chemotherapy to prevent side effects and treat nausea may cause weight gain, says Dale Shepard, MD, medical oncologist at the Cleveland Clinic. “Steroids can increase the appetite and cause fluid retention, which can cause weight gain,” he explains.

Additionally, he says, some two thirds of the women in this recent study received hormone therapy, which is linked to fluid retention and weight gain. Still, undergoing chemo while taking statins doesn’t necessarily mean you will gain weight. An important limitation of the trial, which the authors state, is that it relied on self-reporting.

Preventing Weight Gain

  • Follow a plant-based diet that is rich in fruits and vegetables, whole grains, chicken, turkey, tofu, fish, and beans, says Erin Laure Jennings, MS, RD, CDN, CSO, an Adult Ambulatory Oncology Registered Dietitian at Montefiore Einstein Center for Cancer Care in New York City. (A plant-based diet also lowers your risk of cardiovascular disease, she points out.)
  • Get moving! “Physical activity is very important,” Jennings adds. “Your goal should be 30 minutes per day or 150 minutes per week of moderate physical activity. If you are trying to lose weight, you should bump it up to 60 minutes per day.”
  • Maintain a normal weight. “Being overweight or obese puts your body in a state of low to moderate inflammation,” says Meghan Garrity, MS, RD, CSO, CDN, an Adult Ambulatory Oncology Registered Dietitian at Montefiore Einstein Center for Cancer Care. She points out: “And when you have chronic inflammation in your body over time, this can cause illness. It’s important to achieve and maintain a healthy weight.”
  • Keep in mind that by following the above tips for preventing weight gain, you also can do your heart good. “If you want to lower your risk of heart disease after chemotherapy, talk to your oncologist,” Shepard says. “The two of you should develop a survivorship plan that will include recommendations for regular exercise and a heart-healthy diet.”

Stephanie Bernik, MD, reviewed this article.


Walker, Molly. Weight Gain Common Among Breast Cancer Survivors. MedPage Today. 15 July 2015.

Gross, Amy L. et al. Weight Change in Breast Cancer Survivors Compared to Cancer-Free Women: A Prospective Study in Women at Familial Risk of Breast Cancer. Cancer Epidemiology, Biomarkers & Prevention. 15 July 2015.

"Types of Tumors." Susan R. Komen. Updated Updated 10/28/15. Accessed 12/7/2015.

Stephanie Bernik, MD. Phone interview on September 23, 2015.

Dale Shepard, MD. email interview on September 25, 2015.

Erin Laure Jennings, MS, RD, CDN. Phone interview on September 26, 2015.

Meghan Garrity, MS, RD, CSO, CDN. Phone interview on September 26, 2015.