More evidence that exercise and diet cut breast cancer risk

When it comes to breast cancer prevention and survival rates, lifestyle continues to be a crucial part of the equation.

A recent review published by the American Institute for Cancer Research not only showed how diet and exercise can help reduce breast cancer risk but also increase the chances of survival after diagnosis. It also may reduce the risk of breast cancer recurrence.

“I thought this was a good study,” said Naomi Kalliath, DO, a breast cancer surgeon at Cape Cod Healthcare Breast Surgery - Hyannis and Cape Cod Healthcare Breast Surgery - Falmouth. “I talk with my patients all the time about the importance of diet and exercise and this study supports those facts.”

Researchers reviewed hundreds of studies from around the world consisting of more than 600,000 women.

The review noted the following results:

• A healthy body weight helps to reduce the risk of breast cancer and improves chances of survival following diagnosis.
• Physical activity may reduce the risk of death after diagnosis, reduce breast cancer recurrence and improve quality of life.
• Eating a healthy diet that includes fiber, whole grains, pulses (beans, lentils, and peas), vegetables and fruits may help improve survival.
• Strong evidence showed that a higher body weight following diagnosis increases the risk of death.

The Benefits of Exercise

“We know that Inflammation can be a trigger for chronic disease and cancer. Exercise reduces inflammation,” she said. In addition, exercise can:

• Improve blood and lymphatic flow,
• Improve your mental health and decrease depression,
• Improve blood pressure,
• Improve sugar levels, and
• Improve heart health and help people feel better.

Most medical groups recommend 20-30 minutes of exercise five days a week that includes one day of strengthening exercise with bands, weights or doing lunges using your own body weight, said Dr. Kalliath.

While that represents the ideal scenario, fatigue and lack of energy following radiation and/or chemotherapy can make you feel depleted and hesitant to exercise, but she urges patients to stick with it.

“I don’t think any type of treatment prevents anyone from doing physical activity,” Dr. Kalliath said. “I tell them to try and get their heart rate up with whatever activity they decide they can do. If they are limited by joint or orthopedic issues, I suggest they find some YouTube videos online such as postpartum Pilates or other exercises that are gentle on your joints.”

“It may sound counterintuitive, but what has helped many of my patients who feel fatigued from radiation or chemotherapy to gain their energy back is having a regular exercise routine,” she said. “It’s the one thing that really helped them.”

Other Benefits

Dr. Kalliath also noted another benefit of exercise is the prevention of lymphedema following axillary or lymph node surgery, although this was not included in the study results.

“Historically, women who have had radiation after lumpectomy or mastectomy or had axillary or lymph node surgery were told not to use or stress the arm on the affected side because it was felt that movement would cause lymphedema,” said Dr. Kalliath. “The evidence-based data now supports using your arm and exercising it to reduce the risk of lymphedema and lessen the severity of the lymphedema if you have it.”

The study noted some evidence that eating more dietary fiber including whole grains, pulses, vegetables and fruits may improve survival. A big change noted in this review showed that eating soy could reduce death risk and breast cancer recurrence risk. Soy foods include tofu, tempeh, edamame and soy beverages.

“Eating a balanced diet means limiting red meat, sugars and processed foods and consuming more anti-inflammatory foods such as vegetables, fruits, and fibers,” said Dr. Kalliath. “In the past, eating soy products was not recommended because excessive intake of soy can affect estrogen in your body, and most cancers are estrogen-positive, which is why we want to limit it. However, this study gave evidence of the benefit of eating soy and suggests high isoflavone (estrogenic compounds in fava beans and soybeans) intake after diagnosis may reduce all-cause mortality, breast cancer mortality, and breast cancer recurrence. This is not the first study supporting isoflavone intake to reduce breast cancer risk, and the physiology is more complex than we previously thought.”