Helping Cancer Survivors Make Informed Choices About Diet and Exercise: Recommendations From the ACS

Many of the 9.5 million cancer survivors in the United States seek advice about food, physical activity, dietary supplements, and complementary nutritional therapies. Recently, the American Cancer Society (ACS) issued a guide that provides clinicians with information that can help these patients make informed choices.¹ Highlights of the report follow.

TREATMENT AND RECOVERY

Nutrition. Prevention of unintentional weight loss and maintenance of normal energy levels are crucial, especially for patients who are undernourished. Anticipate potential nutritional difficulties, and build the dietary plan into the overall treatment strategy. For patients who experience anorexia, more frequent, smaller meals-rather than 3 large meals a day-may help increase intake. Commercially available or homemade nutrient-rich drinks may be helpful for patients who are unable to meet their nutritional needs through regular meals.

Vitamin and mineral supplements. No consensus exists about the benefits and risks of supplement use during cancer therapy. The most prudent course is to advise patients who are receiving chemotherapy or radiotherapy to avoid exceeding the upper limits of the Dietary Reference Intakes for antioxidant vitamins such as C and E.²

Physical activity. Currently, there is no clear evidence regarding the effect of exercise on cancer treatment. Patients with a current exercise program should continue their activities as much as possible. Sedentary patients should start a new program with stretching activities and short walks. Advise patients who are receiving chemotherapy or radiotherapy to begin exercise at a lower intensity and build the activity level slowly. In patients for whom bed rest has been prescribed, physical therapy can help maintain strength and range of motion and may combat fatigue and depression.

AFTER RECOVERY

Nutrition. In most cases, evidence connecting specific food choices and exercise to cancer recurrence or survival is lacking or uncertain. However, following the ACS guidelines for healthy food choices may help reduce the risk of the occurrence of second cancers (Table 1).

Physical activity. Increased physical activity may forestall certain cancers,cardiovascular disease, diabetes, and osteoporosis.^3-6 Guidelines from the ACS regarding physical activity for cancer prevention are outlined in Table 1. It is probable that the relationship between increased physical activity and primary prevention of some cancers, cardiovascular disease, and diabetes also holds true for cancer survivors.

ADVANCED CANCER

Nutrition. Many patients with advanced cancer must modify their diet to meet new nutritional requirements and to accommodate such symptoms as pain, constipation, and anorexia. Consider nutrient-rich drinks in patients who cannot meet their nutritional needs with solid food. Use parenteral nutrition and tube feeding on an individualized basis and with a clear understanding of the risks.

Physical activity. Even modest physical activity may help relieve constipation, increase appetite, and counteract fatigue. However, the evidence is too limited to support general recommendations for exercise in this setting.

SPECIFIC CANCERS

Breast cancer. Among patients with breast cancer, increased adiposity is a significant risk factor for recurrent breast cancer and decreased survival.^7,8 Because weight gain after diagnosis is common,^7,9 encourage patients to maintain a healthy weight.³

Exercise-especially weight training-may help prevent or reverse weight gain.^10-12 A weight loss of 1 to 2 lb per week that does not interfere with treatment should be monitored closely and approved by an oncologist.^13,14 Even if the ideal weight can not be achieved, a 5% to 10% loss in body weight over 6 to 12 months reduces elevated plasma lipids and high fasting insulin levels. Encourage moderate activity levels during and after treatment to maintain lean muscle mass, avoid excess body fat, and enhance quality of life.

While alcohol consumption is associated with a modest risk of primary breast cancer,⁷ moderate alcohol consumption (1 to 2 drinks a day) lowers the risk of cardiovascular disease. Data linking alcohol and risk of recurrence and survival are limited.⁷

Data that support an association between dietary fat and risk of breast cancer recurrence are inconsistent,^15,16 although limiting intake of saturated fat is important, because breast cancer survivors are at increased risk for cardiovascular disease.^6,17 Evidence of a link between increased fruit and vegetable intake and lowered risk is conflicting.^18,19 In moderate amounts, soy appears to be neither beneficial nor harmful; however, more than 3 servings a day may have an estrogenic effect,²⁰ which increases the risk of breast cancer progression.²¹ Advise breast cancer survivors to consume a diet high in vegetables and fruits, low in saturated fat, and moderate in soy products.

Colorectal cancer. The risk of colorectal cancer is increased by diets high in red meat and saturated fats and low in fruits and vegetables, sedentary lifestyle, obesity, and possibly excess alcohol consumption.²² However, it is currently unknown whether these factors affect the prognosis for colorectal cancer survivors. The risk of recurrence of colorectal cancer is increased slightly in smokers and in those who have 1 alcoholic drink per day, but it is significantly increased in smokers who also consume more than 1 alcoholic drink per day.²³

Currently, no evidence shows that antioxidant vitamins, fiber supplements, or modest increases in fruit and vegetable intake prevent new polyp growth during a 3- to 4-year period.²⁴ Calcium supplements have been shown to provide a modest benefit in preventing polyp growth.²⁵ Refer to a registered dietitian patients with a history of bowel problems or those undergoing surgery that affects normal nutrient absorption.

Exercise is likely beneficial in reducing the risk of second primary colorectal cancer and in increasing the overall survival. Advise patients to maintain a healthy weight, eat a well-balanced diet consistent with guidelines for cancer and heart disease prevention, and participate in regular physical activity.

Lung cancer. While lung cancer is largely associated with cigarette smoking, there is also a link with diets low in vegetables and fruits.²⁶ During treatment and the immediate recovery period, a diet of smaller, more frequent meals of calorie- concentrated, easy-to-swallow foods is helpful. Recommend a multivita-min supplement for patients who are not meeting their nutritional needs through food; omega-3 fatty acid supplements and additional nutritional support are appropriate for patients with unintentional weight loss.²⁷

Prostate cancer. A decreased intake of saturated fat and an increased intake of fruits and vegetables can lower the risk of cardiovascular disease, a leading cause of death in prostate cancer survivors.^21,28 Small stud-ies of flaxseed oil (Table 2) and soy showed that they inhibited prostate cancer growth, but their effects on prognosis are unknown.²⁸ One study showed an association between vitamin E and a reduced risk of primary prostate cancer and aggressive disease, but there was no effect on survival.^29,30 A small trial found that selenium supplements reduced prostate cancer incidence.^31,32

Men with high calcium intakes, either from diet or supplements, might be at heightened risk for prostate cancer and aggressive disease.³³ The role of calcium after diagnosis is currently unknown. Prostate cancer survivors undergoing androgen- suppressive therapy are at high risk for osteoporosis, but it is not known whether calcium or vitamin D would be beneficial in this setting.

In one study, mortality was higher among overweight prostate cancer survivors.³⁴ Weight control and increased physical activity may prevent other chronic diseases and improve overall survival. n

References:

REFERENCES:

1. Brown JK, Byers T, Doyle C, et al. Nutrition and physical activity during and after cancer treatment: an American Cancer Society guide for informed choices. CA Cancer J Clin. 2003;53:268-291.

2. Monsen ER. Dietary reference intakes for the antioxidant nutrients: vitamin C, vitamin E, selenium, and carotenoids. J Am Diet Assoc. 2000;100:637-640.

3. USDA Dietary Guidelines for Americans. 5th ed. Rockville, Md: US Dept of Health and Human Services; 2000:239. Home and Garden Bulletin no. 232.

4. World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition and the Prevention of Cancer: A Global Perspective. Washington, DC: American Institute for Cancer Research; 1997.

5. World Health Organization. Diet, Nutrition and the Prevention of Chronic Diseases: Report of a Joint WHO/FAO Expert Consultation. Geneva: WHO; 2003. WHO technical report series 916.

6. Krauss RM, Eckel RH, Howard B, et al. American Heart Association Dietary Guidelines: revision 2000: a statement for healthcare professionals from the Nutrition Committee of the American Heart Association. Circulation. 2000;102:2284-2299.

7. Rock CL, Demark-Wahnefried W. Nutrition and survival after the diagnosis of breast cancer: a review of the evidence. J Clin Oncol. 2002;20:3302-3316.

8. Goodwin PJ, Boyd NF. Body size and breast cancer prognosis: a critical review of the evidence. Breast Cancer Res Treat. 1990;16:205-214.

9. Demark-Wahnefried W, Rimer BK, Winer EP. Weight gain in women diagnosed with breast cancer. J Am Diet Assoc. 1997;97:519-529.

10. Demark-Wahnefried W, Kenyon AJ, Eberle P, et al. Preventing sarcopenic obesity among breast cancer patients who receive adjuvant chemotherapy: results of a feasibility study. Clin Exerc Physiol. 2002; 4:44-49.

11. Goodwin P, Esplen MJ, Butler K, et al. Multidisciplinary weight management in locoregional breast cancer: results of a phase II study. Breast Cancer Res Treat. 1998;48:53-64.

12. McTiernan A, Ulrich C, Kumai C, et al. Anthropometric and hormone effects of an eight-week exercise-diet intervention in breast cancer patients: results of a pilot study. Cancer Epidemiol Biomarkers Prev. 1998;7:477-481.

13. McTiernan A, Ulrich C, Slate S, Potter J. Physical activity and cancer etiology: associations and mechanisms. Cancer Causes Control. 1998;9:487-509.

14. Irwin M, Yasui Y, Ulrich CM, et al. Effect of moderate- and vigorous-intensity exercise on total and intra-abdominal body fat in postmenopausal women: a one-year randomized controlled trial. JAMA. 2003;289:323-333.

15. Smith-Warner S, Spiegelman D, Adami H, et al. Types of dietary fat and breast cancer: a pooled analysis of cohort studies. Int J Cancer. 2001;92: 767-774.

16. Kushi L, Giovannucci E. Dietary fat and cancer. Am J Med. 2002;113:63S-70S.

17. Brown BW, Brauner C, Minnotte MC. Noncancer deaths in white adult cancer patients. J Natl Cancer Inst. 1993;85:979-997.

18. Petrakis N, Barnes S, King E, et al. Stimulatory influence of soy protein isolate on breast secretion in pre- and post-menopausal women. Cancer Epidemiol Biomarkers Prev. 1996;10:785-794.

19. Messina M, Loprinzi C. Soy for breast cancer

survivors: a critical review of the literature. J Nutr.

2001;131:3095S-3108S.

20. Gandini S, Merzenich H, Robertson C, Boyle P.

Meta-analysis of studies on breast cancer risk and diet: the role of fruit and vegetable consumption and the intake of associated micronutrients. Eur J Cancer. 2000;36:636-646.

21. Smith-Warner SA, Spiegelman D, Yaun SS, et al. Intake of fruits and vegetables and risk of breast cancer: a pooled analysis of cohort studies. JAMA. 2001;285:769-776.

22. Potter J. Nutrition and colorectal cancer. Cancer Causes Control. 1996;7:127-146.

23. Baron JA, Cole BF, Mott L, et al. Neoplastic and antineoplastic effects of beta-carotene on colorectal adenoma recurrence: results of a randomized trial. J Natl Cancer Inst. 2003;95:717-722.

24. Byers T. What can randomized controlled trials tell us about nutrition and cancer prevention? CA Cancer J Clin. 1999;49:353-361.

25. Baron J, Beach M, Mandel J, et al. Calcium supplements for the prevention of colorectal adenomas. Calcium Polyp Prevention Study Group. N Engl J Med. 1999;340:101-107.

26. Ziegler RG, Mayne ST, Swanson CA. Nutrition and lung cancer. Cancer Causes Control. 1996;7: 157-177.

27. Brown JK. A systematic review of the evidence on symptom management of cancer-related anorexia and cachexia. Oncol Nurs Forum. 2002;29:517-530.

28. Demark-Wahnefried W, Price DT, Polascik TJ, et al. Pilot study of dietary fat restriction and flaxseed supplementation in men with prostate cancer before surgery: exploring the effects on hormone levels, prostate-specific antigen and histopathologic features. Urology. 2001;58:47-52.

29. The Alpha-Tocopherol, Beta carotene Prevention Study Group. The effect of vitamin E and betacarotene on the incidence of lung cancer and other cancers in male smokers. N Engl J Med. 1994;330: 1029-1035.

30. Heinonen OP, Albanes D, Virtamo J, et al. Prostate cancer and supplementation with alpha- tocopherol and beta-carotene: incidence and mortality in a controlled trial. J Natl Cancer Inst. 1998;90: 440-446.

31. Clark LC, Coombs GF Jr, Turnbull BW, et al. Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin. A randomized controlled trial. National Prevention of Cancer Study Group. JAMA. 1996;276:1957-1963.

32. Clark L, Dalkin B, Krongrad A, et al. Decreased incidence of prostate cancer with selenium supplementation: results of a double-blind cancer prevention trial. Br J Urol. 1998;81:730-734.

33. Giovannucci E, Rimm E, Wolk A, et al. Calcium and fructose intake in relation to risk of prostate cancer. Cancer Res. 1998;58:442-447.

34. Calle EE, Rodriguez C, Walker-Thurmond K, Thun MJ. Overweight, obesity and mortality from cancer in a prospectively studied cohort of US adults. N Engl J Med. 2003;348:1625-1638.

35. University of Texas M. D. Anderson Cancer Center. Herbal/Plant Therapies: Ginger(Zingiber officinale Roscoe). Natural Standard Patient Monograph; 2002. Available at: http://www.mdanderson. org/departments/CIMER. Accessed May 14, 2004.

36. Miller LG. Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med. 1998;158: 2200-2211.

37. Bushman J. Green tea and cancer in humans: a review of the literature. Nutr Cancer. 1998;31:151-159.

38. Jatoi A, Ellison N, Burch PA, et al. A phase II trial of green tea in the treatment of patients with androgen dependent metastatic prostate carcinoma. Cancer. 2003;97:1442-1446.