University at Buffalo (UB)
Release Date: October 31, 2003 This content is archived.
BUFFALO, N.Y. -- Is exercise good or bad for cancer survivors? Should they eat hearty or restrict calories to speed recovery and prevent recurrence? Is a glass of wine a bad thing?
Jean K. Brown, Ph.D., associate professor of nursing and nutrition at the University at Buffalo, headed a panel established by the American Cancer Society to answer these and many other questions concerning what persons who have survived cancer can do to lower their risk of recurrence and how those living with cancer can experience life to the fullest.
Their recommendations appear in the September-October issue of CA: A Cancer Journal for Clinicians.
"After a diagnosis of cancer, survivors soon find that there are few clear answers to their questions about nutrition and physical activity," said Brown. "Our goal was to give oncology health-care providers and cancer survivors accurate information upon which to make informed decisions regarding nutrition and physical activity during the cancer-survival continuum -- treatment, recovery, preventing recurrence and/or living with advanced cancer."
The society convened the 19-member panel to assess the scientific evidence and best clinical practices relating to nutrition and physical activity after a cancer diagnosis. Brown is a lead researcher on the first national, large-scale study of quality-of-life issues, including nutrition, affecting women with lung cancer. She also has studied cancer-related weight loss during radiation therapy with Peter Horvath, Ph.D., a UB colleague.
The recommendations address body weight, nutrition, food safety, dietary supplements and alternative therapies for cancer survivors in general, and offer specific guidelines for survivors of breast, prostate, lung, colorectal and gastrointestinal cancers.
The general recommendations are similar to those pertaining to the population at large, making allowances for the physical demands of cancer treatment and recovery:
* Maintain a healthy weight
* Follow a diet low in saturated fat and high in fruits, vegetables, whole grains and fiber
* Include a daily multiple vitamin
* Take part in physical activity appropriate for one's age, state of fitness, type of cancer, type of treatment and any additional health problems.
The recommendations call for at least 30 minutes of moderate activity on at least five days a week, with breast- and colon-cancer survivors further reducing their risk of recurrence by increasing activity time to 45 minutes or more of moderate to vigorous activity five or more days a week.
In addition, the panel arrived at some specific guidelines that pertain to all types of cancer, including:
* Survivors with severe anemia should not exercise until the condition improves
* Persons with compromised immune systems resulting from chemotherapy should avoid public places
* Those receiving radiation therapy, which can irritate skin, should not swim in chlorinated pools.
Guidelines for specific cancers vary according to type. For breast cancer, the most important risk factor is obesity. This is particularly problematic, Brown noted, because many women gain weight after breast-cancer diagnosis, and treatment with tamoxifen, now prescribed routinely, usually causes weight gain.
"Excess body weight may be the most important avoidable factor relating to nutrition and physical activity that affects breast-cancer survival," Brown stated. "In a large cohort study of women with breast cancer, women in the highest weight quintile with stage I disease had a 70 percent increased risk of dying of breast cancer, and women with stage II disease has a 40 percent increased risk of dying."
The combination of smoking cigarettes and drinking more than one alcoholic beverage per day produces a significant increase in risk for colorectal cancer, the guidelines state, while calcium supplements appear to provide modest benefit in preventing new polyps, and physical activity may help prevent primary colon cancer. The most significant risk factor for survival among lung cancer patients, other than smoking cigarettes, is weight loss, said Brown. The guidelines encourage survivors to consume small, but frequent, meals providing concentrated calories, such as foods high in fats, and to take multivitamin-mineral supplements.
The most consistent association of prostate cancer and nutritional factors involves saturated fat. The guidelines advise prostate-cancer survivors to avoid such foods, to consume diets rich in fruits and vegetables and to remain physically active. These lifestyle habits also help to protect against cardiovascular disease, a major cause of death in prostate-cancer survivors, Brown noted.
The panel found little evidence regarding measures that may help protect against recurrence of cancers of the head, neck and upper digestive tract (esophagus, stomach and pancreas.) The guidelines recommend adopting the standard, positive lifestyle habits of eating a healthy diet containing plenty of fruits and vegetables, maintaining the optimum weight for height and remaining active.
For their own comfort, survivors of esophageal cancer, who often suffer gastric reflux, are advised to eat a high-protein, low-fat, high-carbohydrate diet and to avoid chocolate, fat, alcohol, coffee, spearmint, peppermint, garlic and onion, Brown said. Survivors of head and neck cancers, who often have trouble biting, chewing and swallowing, and thus may not get enough nutrients, should avoid acidic, salty, spicy and very hot or cold foods, which could make eating more difficult, she added.
In the final analysis, the guidelines make clear that despite all the research conducted on cancer, there still is no incontrovertible evidence that any lifestyle intervention will prolong the life of cancer survivors. The best plan, said Brown, is simply to stay as healthy as possible and use common sense: eat right, maintain an optimal weight and remain active.