Some survivors experience weight gain during or after cancer treatment; learn why it is important to maintain a healthy weight and about the support to help you do it.

As a breast cancer survivor, Rhonda Spinks was surprised to learn that weight gain was a possible side effect of treatment.

“I hadn’t thought of gaining weight as a side effect of cancer,” says the Oklahoma City resident. “I thought of cancer as related to weight loss, so gaining was the opposite of what I expected.”

Rhonda, a wildlife biologist and captain of a U.S. Army medical unit, did, however, gain weight during treatment for stage III breast cancer. “I gained a significant amount of weight during the first month of chemotherapy,” she says.

Rhonda’s experience is not unique: Research has shown that with breast cancer in particular, 50 to 96 percent of patients gain weight at some point during or after treatment.1

What Leads to Weight Gain?

According to Kristen Trukova, MS, RD, LDN, CNSC, CSO, Clinical Oncology Dietitian at Cancer Treatment Centers of America® (CTCA) in Zion, Illinois, many factors can contribute to a patient’s weight gain during treatment for breast cancer. Research into the issue has identified two main culprits: a major decrease in physical activity and the effects of treatment on metabolism.

For example, chemotherapy can contribute to early menopause, which leads to metabolic changes, making it difficult to maintain a healthy body weight. Certain hormonal treatments can also trigger early menopause, and patients who are treated with a hysterectomy (surgery to remove the uterus) will go through menopause immediately. In addition, steroids—another potential culprit in weight gain—are sometimes used as part of chemotherapy.

Rhonda suspects that her strong cravings while she was in treatment—especially for bread and processed, sugary foods—were the major culprit in her case. She also could not exercise at her usual level of intensity.

Emotions are another factor that can have considerable influence over how and what survivors eat, also potentially leading to weight gain. Survivors may eat for comfort, says Sarah Kiser, MS, RD, Clinical Oncology Dietitian at CTCA® in Goodyear, Arizona. Additionally, emotional reserves may be depleted, leading to a less considered, more impulsive approach to meals and snacks. “Patients might choose whatever food appeals most, and that may not include the most nourishing foods,” Kiser says of the tendency toward comfort foods.

On the other hand, as a way to celebrate, patients might overeat or indulge too much when they start to feel good again. And because chemotherapy can affect taste buds, you might be challenged to restrain yourself from your favorite flavors when you can taste them again. If nausea and vomiting (a common side effect of chemotherapy) have curbed your pleasure in food, you may also find yourself going overboard as this side effect goes away. “It’s okay to enjoy comfort food,” says Kiser, but in moderation. “It’s still important to make healthy choices the majority of the time.”

The Importance of a Healthy Weight

From quality of life to long-term health and prevention of recurrence, there are countless reasons for maintaining a healthy weight—during cancer treatment, as possible, and beyond, says Trukova. “Obesity is a risk factor for cancer,” she explains, “and there’s evidence that obesity increases risk for recurrence.”2

Rachel Winston, MS, RD, Clinical Oncology Dietitian, who works with Kiser at CTCA in Goodyear, refers to guidelines from the American Institute for Cancer Research (AICR; linking excess adipose tissue to an increased risk of certain cancers as well as other chronic diseases, such as diabetes.

The AICR’s recommendations for cancer prevention include: “Be as lean as possible without becoming underweight” and “Be physically active for at least 30 minutes every day.” Winston says that these measures not only help prevent future cancers but also boost your self-esteem and sense of empowerment. Plus, she says, “Optimizing your nutritional intake can help improve energy and mood.”3

Trukova adds that cancer can also have an impact on your body image, whether that is due to physical changes like a mastectomy or colostomy or a changed attitude toward your body. As a result, she says, “Maintaining a healthy weight is an important part of a good quality of life.”

Rhonda certainly felt the impact of a changed body image. “I was active before, then couldn’t work out as hard as I wanted,” she says. This not only made it hard to control her weight but also influenced how she felt about herself. “It was frustrating,” she says, “because I didn’t want to be treated like a sick person. I wanted to stay active to show the world I’m fine.” Before her diagnosis, Rhonda explains, “Being fit and strong was part of my identity.”

Tips for Keeping a Healthy Weight during and after Treatment

Rhonda successfully returned to a healthy weight by continuing to exercise, even though she had to scale back her workouts when she was not feeling her best. “I stayed active within my current capacity,” she says, explaining that she would adjust her routine with changes such as walking instead of running.

She also set goals. “I was determined to be more fit and active than ever,” she says. And she has seen this ambition through by becoming a competitive body builder since finishing treatment. Rhonda entered her first body-building competition in 2014—five years after her diagnosis.

Kiser supports an approach like Rhonda’s—namely, to stay active as appropriate for your current strength and energy levels. “I encourage a healthy routine within your ability,” she says, adding that survivors may want to work with a physical therapist to create safe exercise routines.

Nutrition is, of course, also an important part of maintaining a healthy weight. Winston says that a dietitian can help you establish healthy eating habits during and after treatment. She also directs patients to the AICR dietary guidelines, which provide great information and recipes, including tips for eating mostly plant-based foods (vegetables, fruit, whole grains and beans), limiting red meat and avoiding processed meats. In addition, AICR offers insight into research related to food choices that may help prevention efforts in its “Foods That Fight Cancer” list. Some foods that might protect against cancer include blueberries, walnuts, wild-caught salmon and dark green leafy vegetables.4

Friends and family can do a lot to help you stay on track with nutrition and fitness goals, says Trukova. “Engage a friend or family member,” she recommends. “Share your goal and ask for their help achieving it.” She says that simple things like having someone call to check in regularly can help you build healthy habits.

Trukova says that you can also hold yourself accountable for your food and activity choices by keeping a journal of everything you eat and how much you are exercising. “Logging food [and activity] can make you more mindful and see patterns,” she explains. You may see in these patterns places where you can make changes and a real difference.

Organizations like Weight Watchers that require a regular weigh-in can also help keep you working toward your goal, says Trukova. And don’t forget your care team—the doctors, dietitians, physical therapists and nurses involved in your treatment can be an ongoing source of support and information.

If you are having trouble getting moving, Winston suggests looking to community organizations and events to make exercise fun and supportive and to create some structure. Consider, for example, local running or walking groups, or gather a group of friends who enjoy the same activities. Winston also says that cancer advocacy events (runs or walks to raise money and awareness for a particular cause) can offer a fun atmosphere and can serve as fitness goals.

Worth Every Effort

Whether your journey is from cancer patient to competitive body builder or survivor looking to staying healthy, the process is not always easy. But outcomes like Rhonda’s can help you remember the importance and reward of this commitment. “I feel really great about my health—healthier than I’ve ever been,” Rhonda says. “I’ve learned the importance of being proactive about health.”

1. Vance, V., Mourtzakis, M., McCargar, L., & Hanning, R. (2011). Weight gain in breast cancer survivors: Prevalence, pattern and health consequences. Obesity Reviews, 12, 282–294. doi: 10.1111/j.1467-789X.2010.00805.x
2. De Pergola, G., & Silvestris, F. (2013). Obesity as a major risk factor for cancer. Journal of Obesity. doi: 10.1155/2013/291546
3. Recommendations for Cancer Prevention. American Institute for Cancer Research. Retrieved March 23, 2015, from cancer-risk/recommendations-for-cancer-prevention
4. Diet—What We Eat. American Institute for Cancer Research. Retrieved March 23, 2015, from