Denver, CO—Obesity is about to overtake tobacco as a modifiable risk factor for cancer. Approximately 30% of cancers could be prevented by maintaining a normal weight and healthy lifestyle, according to 2 experts who spoke at the 42nd annual meeting of the Oncology Nursing Society. They also asserted that nurses can play a role in motivating patients to lose weight.
“This is a sensitive topic to bring up with patients, but it is a very important one. Obese and overweight patients are less likely to seek medical care and less likely to participate in screening programs,” explained Anne Katz, PhD, RN, FAAN, Clinical Nurse Specialist, Dr Ernest W. Ramsey Manitoba Prostate Centre, Winnipeg, Canada, and Editor of Oncology Nursing Forum.
Obese patients have poorer quality imaging, problems assessing tumor markers, and technical problems with radiation and surgery.
Obese, postmenopausal women are twice as likely to develop breast cancer and have a >30% likelihood of dying from cancer and other causes than women with normal weights, Dr Katz said.
“Weight gain is common after developing breast cancer, and this increases the risk of recurrence, death, cardiovascular disease, hypertension, and developing metabolic syndrome,” she continued.
In addition, obese women with breast cancer tend to have poorer responses to aromatase inhibitors, and more adverse events than their normal-weight counterparts. In prostate cancer, obesity is related to mortality, disease progression, and more aggressive disease.
For breast, prostate, gynecologic, renal, and hematologic cancers, obesity is associated with less favorable outcomes and higher recurrence rates.
Lifestyle and Diet
“About one-third of all cancers can be prevented by maintaining healthy dietary habits,” said Amanda Bontempo, MS, RD, CSO, CDN, Registered Dietitian, New York University Langone Medical Center.
General recommendations for patients with cancer are to:
- Be as lean as possible without becoming underweight
- Be physically active for >30 minutes daily
- Avoid sugary drinks
- Limit consumption of energy-dense, salty, and processed foods
- Limit intake of red meats and avoid processed meats
- If consumed at all, limit alcoholic drinks to 2 for men and 1 for women daily
- Do not use supplements to protect against cancer
- Do not smoke or chew tobacco.
“Replace processed foods with whole foods. It is cheaper and easier. Products are hyped with sugar. There are 56 different names for sugars that can be added to foods, and this can be hidden in the ingredient list. Eighty percent of the sodium we consume comes from processed foods,” said Ms Bontempo.
“We cannot allow ourselves to become entrenched in the idea to just count calories. The types of food we eat are important and have the ability to alter our metabolism,” she added.
For example, a daily serving of red meat (including pork and goat) increases the risk for colorectal cancer by 10%; 4 pieces of bacon eaten daily increases the risk for colorectal cancer by 15%.
“The maximum recommendation for red meat is 18 ounces per week,” Ms Bontempo stated.
Nurses can encourage patients about the importance of maintaining an optimal lifestyle, which takes time, planning, and dedication.
“Small steps can make a big impact,” she noted.
These steps have been well-documented in the literature, but bear repeating:
- Eat a variety of vegetables, fruits, whole grains, and legumes (eg, beans; berries; allium, cruciferous, and dark green leafy vegetables; tomatoes; green tea; and turmeric)
- Eat fatty fish and healthy fats
- Limit contaminants and buy organic when possible; >400 carcinogenic chemicals and pesticides are used in foods
- Check vitamin D levels, because vitamin D deficiency is associated with increased risk for cancer.
“No one diet will prevent cancer, but if patients can start to incorporate these recommendations, they will reduce their risk,” Ms Bontempo said.
The Last Taboo
Obesity and being overweight are very difficult subjects to discuss with patients, acknowledged Dr Katz, but she asserted that cancer is a “teachable moment.”
Nurses are often uncomfortable tackling this subject, and patients are uncomfortable talking about it. Dr Katz suggested empathizing with patients.
“I struggled with my weight my entire life. I understand how hard it is. If you have struggled with your weight, use it as a bridge for discussions with patients,” she advised.
“Patients and families feel powerless, and they want to do something to give them a sense of control. They may ask, ‘What can I do to help myself? What can I do to help my partner?’” Dr Katz continued.
Timing of the conversation about weight is critical. Do not start this discussion at the time of diagnosis when patients are overloaded and cannot take in everything they are being told.
“Weight control should be discussed again and again, through cancer care and survivorship,” Dr Katz stated.
Several different models have been proposed for discussions with patients about weight, and they all have common themes. Suggestions for opening discussions include using open-ended questions, not being judgmental, establishing trust and collaboration, acknowledging the patient’s struggles, respecting the patient, and, if the patient is ready, establishing action points that support behavioral change.
Nurses are not dietitians. Refer the patient to appropriate resources, and tell them that many diets are similarly effective. Each patient needs to find a diet that works for them. Resources include materials from the American Society of Clinical Oncology, the Oncology Nursing Society, and Dr Katz’ new book, A Healthcare Provider’s Guide to Cancer and Obesity.