A review of evidence-based practice in nutrition related complementary therapies: improving the knowledge of dietitians

Authors:

Details:

Department of Nutrition and Dietetics, Royal Brisbane and Women’s Hospital, Queensland.


Abstract

Use of complementary and alternative medicine in cancer continues to increase and there is a need for health professionals to provide evidence-based information. The aim of this review was to determine whether nutritional supplementation, as a complementary and integrative therapy during oncology treatment, has either improved or adversely affected outcomes. A literature review and appraisal of the hierarchy of evidence until February 2010 were undertaken, excluding individual studies, animal studies, in vitro studies and anecdotal reports. The search results included 52 articles for inclusion. The summary of evidence was divided into four main sections: supplements that had a potential positive effect and no evident harm, supplements that had a potential positive effect but also had side-effects, supplements that had no effect, and supplements that had potential negative/harmful effects. There is a significant volume of evidence concerning nutrition related complementary therapies, however the evidence is generally weak and there are multiple variables making it difficult to extrapolate generalised recommendations for any one type of supplement. The challenge remains to provide strong evidence to support complementary and integrative therapy as part of integrated mainstream treatment therapies.


Complementary and alternative medicine (CAM) is defined as a group of diverse medical and health care systems, practices and products not presently considered to be part of conventional medicine.1 Complementary therapies are used together with conventional medicine, whereas alternative medicine is used in place of conventional medicine and is therefore generally not recommended.1 Integrative medicine combines conventional and CAM treatments where there is evidence of safety and effectiveness.1 Perhaps a more encompassing and emerging term is complementary and integrative therapies (CIT) because it blends evidence-based complementary therapies with conventional medicine.

People with cancer may use CAM in an effort to: treat their cancer; reduce treatment toxicities; improve cancer related symptoms; foster the immune system; assist with quality of life/coping; prevent recurrence; or treat non-cancer related conditions such as arthritis, heart disease and insomnia.2-6 Types of CAM include nutrition related therapies such as herbal medicines/botanicals, vitamins, minerals, special diets and other natural products including probiotics/enzymes. Non-nutritional types of CAM include mind-body medicines such as meditation, yoga, acupuncture, manipulation and body-based practices such as spinal manipulation and massage, along with other practices such as energy therapy, magnets, art, music and spirituality.1

The use of CAM by people with cancer varies significantly in the literature (7% to 91%),7-12 partly due to considerable differences in definitions/research methodology, practice disclosure issues and because the popularity of CAM continues to increase.13 A recent Australian study found that 65% of cancer patients used at least one form of CAM, the most common type being nutritional supplements.14 Despite common medical concerns, reports of adverse effects from the use of CAM in this study were rare (3%) and reported perceived benefits common (90%).14 This study also reported that most patients (90%) agreed that medical doctors should consider learning about CAM to provide appropriate advice to their patients, highlighting the need to assist clinicians to provide evidence-based information.14

Another recent study conducted in Asia found that 71% of participants did not discuss their CAM use with their oncologists, mainly because the doctor never asked, 29% did not discuss with any healthcare providers and 64% obtained advice from friends/families.15When the issue was discussed, 73% of oncologists did not encourage using CAM, especially during radiotherapy.15 This study suggested that oncologists should initiate discussion in a non-judgemental manner so as to encourage disclosure and highlighted the need for high quality communication.15 

Numerous guidelines have been published on communication and decision making regarding CAM.16-18 Health professionals should be informed about commonly used CAM and be able to access evidence-based information on potential benefits, harm and interactions, to advise patients accordingly.15,16 Health professionals should be proactive in discussing with patients how well they are coping and the use of CAM.15 Being open minded, using effective communication skills, and working together as a team appear vital for an improved patient journey and outcomes.16,18

Some may question which health professionals’ role/scope of practice includes CIT, and it appears pertinent that all team members play a part and remain up-to-date with professional development in this area. Dietitians are ideally placed to have open dialogue with patients on CIT, especially nutrition related therapies, and to assist with decision making. Basic training for dietitians includes chemistry, physiology, evidence-based practice and literature appraisal, communication and counselling skills, and complex decision making skills. In addition, dietitians are well placed members of the multidisciplinary team, liaising regularly with medical, nursing and allied health staff, including pharmacists, and could act as patient advocates to discuss CIT with all team members. 

Currently in clinical practice, dietitians are frequently asked by patients for advice on CIT. The aim of this review is to determine whether nutritional supplementation as a CIT during any type of oncology treatment has either improved or adversely affected outcomes for patients. With this increased knowledge, it is proposed that dietitians would feel more comfortable and confident in discussing CIT with their patients.

Search criteria

A literature review was performed including relevant guidelines, summaries (via Up-To-Date, British Medical Journal clinical evidence), synopses, syntheses and systematic reviews (via Evidence-based medicine reviews, Cochrane Library, Pub Med Clinical Queries), and hand searching of reference lists of those articles retrieved. Search terms included ‘cancer’ and any form of oral nutrition supplement eg. vitamins, minerals, micronutrients, herbs, antioxidants, fish oils, carotenoids, flavonoids, or soy, and also included medical subject headings. Inclusions were English language and human studies. Exclusions were parenteral nutrition or enteral nutrition with supplements added, eicosapentaenoic acid in relation to cancer cachexia (as guidelines already published), 19and primary prevention trials. The hierarchy of evidence was searched up until February 2010 and limited to higher levels of evidence. Grey literature was not within the scope of this review and individual studies for each therapy, animal studies, in vitro studies and anecdotal reports were excluded.  Following article retrieval, the evidence was appraised using the National Health and Medical Research Council’s levels and grades of evidence.20 Each paper was reviewed independently by both authors and consensus was reached on the levels/grades of evidence.

Current data

The search results included eight existing guidelines, one summary of evidence (via Up-To-Date), eight synopses of evidence (via Evidence-based medicine reviews), 18 syntheses of evidence (via Cochrane) and 12 clinical queries (via Pub Med). Hand searching of reference lists identified a further five papers, resulting in a total of 52 articles for inclusion.

Summation of nutrition related complementary therapy evidence was based on four main categories: supplements that had a potential positive effect and no evident harm (see table 1); supplements that had a potential positive effect but side-effects (see table 2); supplements that had no effect (see table 3); and supplements that had potential negative/harmful effects (see table 4). 

 Table 1: Supplements with potential positive effect and no evident harmTable 1: continued Table 2: Supplements with potential positive effect but have side effectsTable 2: continuedTable 2: continued Table 2: continued   Table 3: Supplements with no effect  Table 4: Supplements with potential negative/harmful effectsTable 4: continued

As seen in table 4, there is strong evidence (Grade A) concerning a small number of nutrition related therapies. High dose supplements of vitamins, minerals and other bioactive compounds do not have any specific benefits seen in the research (Grade A) and there is expert opinion concerning potential negative/harmful effects. In addition, phyto-oestrogens to treat breast cancer have shown no benefit on easing symptoms such as hot flashes (Grade A) and some experts believe it might stimulate tumour growth and should be avoided in breast and endometrial cancers. Of great concern is that antioxidant supplementation during and after cancer treatment may increase the incidence of some cancers (Grade A), including bladder and lung (with beta carotene).

Implications

It appears that evidence concerning nutrition related CIT during oncology treatment is generally quite weak, with a few exceptions. Specifically, high dose supplements and phyto-oestrogens have shown no benefits, while antioxidants may increase the incidence of some cancers. These conclusions may be due to the lack of large randomised control trials and the sheer number of variables that need consideration in this area of research. These include supplement type/dose/timing, tumour stream and stage, treatment type, and other medications/treatments that potentially could interact. These multiple factors also make it difficult to extrapolate broad recommendations for any one type of supplement.

Much of the research conducted to date is not sufficiently detailed to provide strong conclusions for practice. For example, much of the research around antioxidants does not outline specifics and as further evidence comes to light, these factors appear pertinent. Some antioxidants including vitamin E, melatonin, amifostine and glutathione supplementation during chemotherapy may assist with reducing dose limiting toxicities. However, antioxidant supplementation during radiotherapy may be associated with reduced local tumour control and survival, especially vitamin E with head and neck cancer.

The implication from these finding for oncology dietitians in practice is that they should be as specific as possible when reviewing the research and encourage patients to consider all factors relating to supplement type, tumour stream and treatment plan, in decision making. There is also an ethical obligation to ensure patients are well informed, particularly where there is strong evidence of supplements with potential negative/harmful effects, and to clearly emphasise the importance of specificity. Additionally, personal circumstances need to be considered and advice should be individualised.

It appears that many of the recommendations in the literature concerning potential side-effects, toxicities and interactions are based on expert opinion. One would think this is due to the ethical difficulties in conducting randomised trials in this area, especially if there is a theoretical risk of harm. There is a tendency for health professionals to discourage patients from taking supplements altogether if there is any risk of harm. However, it is worthwhile considering the basis for the expert opinion and the relevant applicability to individuals’ circumstances. For example, is the risk a theoretical risk, has it been seen in animal studies only, or reported in individual participants in human case studies, or in research outcomes.

Traditionally, CIT has probably been outside of the scope of practice for most dietitians.  However, with the rise of evidence-based therapies such as medical nutrition therapy and more recently functional nutrition therapy, where active nutrients, ingredients and functional foods are used in a therapeutic manner to address nutritional deficiencies and nutrition-related problems, dietitians need to be approachable and keep abreast of current developments and trends, in order to guide patients through what can be a very complex decision making process. Oncology dietitians should endeavour to include CIT in their regular professional development in this fast growing area.

Patients will often weigh up the benefits and risks themselves. For example, a patient suffering from severe fatigue may choose to take ginseng despite expert advice that it may cause emesis, headaches and interact with anticoagulation medications. The requirement for oncology dietitians is to encourage patients to consider the basis for reported potential harm, and to liaise with other members of the multidisciplinary team who may be more knowledgeable in this area, such as medical staff and pharmacists. There are also a number of databases/websites available. Individual supplements may be assessed for potential interactions/side-effects. Patients may thereby be provided with useful information to assist in decision making. Examples include the Natural Medicines Comprehensive Database,55 the Memorial Sloan-Kettering Cancer Centre website,56 the National Centre for Complementary and Alternative Medicine website,57 the Office of Cancer Complementary and Alternative Medicine website,58 and the Therapeutic Goods Administration website.59

Additionally, dietitians should refer patients to qualified CIT practitioners, however this may be more difficult in Australia than in other countries throughout Asia, America and Europe where CIT practitioners often work side-by-side with the traditional multidisciplinary team. CIT practitioners should have completed the relevant education and be a member of a professional association. For example, an association with high entry standards for naturopaths/herbalists is the National Herbalists Association of Australia. In addition, some naturopaths have completed degrees or post doctoral study and it would be ideal for dietitians to determine if any such practitioners are located in their area. There is also the Australian Acupuncture and Chinese Medicine Association and the Chinese Medicine Registration Board of Victoria. Chinese Medicine Practitioners will soon be included in the National Registration Accreditation Scheme in 2012.60 Ideally, people should meet a few CIT practitioners in their local area to find out about their background, experience and training, and then build a referral list to provide diversity. In addition, a referral letter including medical history and treatment plan, medications, and dietary recommendations should be provided to increase patient safety. 

It would also be beneficial for patients and clinicians alike, if more oncology treatment centres throughout Australia would look to integrate qualified CIT practitioners into the more traditional multidisciplinary team structure. One example is the SolarisCare Cancer Support Centre located within the Sir Charles Gardiner Hospital, Western Australia, which opened in 2001 to provide free information, support and supervised complementary therapies in a drop-in community centre style service on a tertiary hospital campus.61 This innovative service, focused on non-nutritional CIT, has demonstrated a positive impact on quality of life and symptom distress.62 Throughout the world, there are numerous other examples of similar integrative services.

The limitations of this review should be acknowledged and considered when interpreting the findings. The scope and methodology excluded non-English publications and due to the use of CIT, for example in parts of Asia and Europe, potentially important information may have been omitted. In addition, individual studies for each therapy and grey literature such as animal studies, in vitro studies and anecdotal reports were also excluded. As this is an emerging area of research, the grey literature could potentially highlight important beneficial findings to explore in higher level studies. Some proponents of CIT may not have the medical model background in evidence-based practice, and may not have conducted research in areas they believe from experience to show benefit.

It appears dietitians are well placed to guide oncology patients through decision making  regarding CIT and that a collaborative effort by the entire multidisciplinary team is needed regarding potential interactions, interpreting the literature and making recommendations for practice. The traditional oncology multidisciplinary team may need to reconsider its scope to engage with CIT practitioners. Such an integrative approach would need cooperation between practitioners in relation to individual patients and the need to support the patient using a sympathetic but evidence-based approach, rather than simply producing barriers which may result in non-disclosure by the patients and a missed opportunity to integrate therapies safely.

As a result of this literature review, the authors plan to integrate the findings into ‘The Integrative Medicine Drug-Complementary Medicine Project’, sponsored by the Complementary and Integrative Therapies Interest Group of the Clinical Oncological Society of Australia. This group comprises pharmacists, naturopaths, herbalists, dietitians, nurses and oncologists. It seeks to undertake comprehensive reviews of the literature to establish the level of evidence suggesting an interaction between three to five key chemotherapeutic agents and the most commonly used herbal and nutritional supplements in Australia. It is hoped that by working together we will be able to foster respect between different practitioners, promote consistent messages to patients, provide more widely available guidelines in this area, and identify clearer evidence-based recommendations for practice to improve the patient journey.

Conclusion

This review found a significant volume of evidence concerning nutrition related complementary therapies, however the strength of the evidence is generally weak. In addition, there are multiple variables that need to be considered in the research, making it difficult to extrapolate recommendations for any one type of supplement. The challenge remains to provide strong evidence to support CIT as part of mainstream treatment therapies. Collaborative engagement between the proponents of CIT and established multidisciplinary teams is needed to enable well designed randomised control trials that include large numbers of patients and relevant clinical endpoints. Further research is also needed in order to map with confidence relevant potential interactions and side-effects.

References

1. National Centre for Complementary and Alternative Medicine. What is Complementary and Alternative Medicine [Internet]? Maryland: National Institutes of Health; updated 2010 November 22 [cited 2011 January 20]. Available from: http://nccam.nih.gov/health/whatiscam/ 

2. Boon H, Stewart M, Kennard MA, Gray R, Sawka C, Brown JB, et al. Use of complementary/alternative medicine by breast cancer survivors in Ontario: prevalence and perceptions. J Clin Oncol. 2000;18:2515-21.

3. Ashinkaga T, Bosompra K, O’Brien P, Nelson L. Use of complementary and alternative medicine by breast cancer patients: prevalence, patterns and communication with physicians. Support Care Cancer. 2002;10:542-8.

4. Shen J, Andersen R, Albert P, Wenger N, Glaspy J, Cole M et al. Use of complementary/alternative therapies by women with advanced-stage breast cancer. BMC Complement Altern Med. 2002;2:8.

5. Henderson JW, Donatelle RJ. Complementary and alternative medicine use by women after completion of allopathic treatment for breast cancer. Altern Ther Health Med. 2004;10:52-7.

6. Molassiotis A, Scott JA, Kearney N, Pud D, Magri M, Selvekerova S et al. Complementary and alternative medicine use in breast cancer patients in Europe. Support Care Cancer. 2006;14:260-7.

7. Ernst E, Cassileth BR. The prevalence of complementary/alternative medicine in cancer: a systematic review. Cancer. 1998;83:777-82.

8. White JD. The National Cancer Institute’s perspective and agenda for promoting awareness and research on alternative therapies for cancer. J Altern Complement Med. 2002;8:545-50.

9. Begbie SD, Kerestes ZL, Bell DR. Patterns of alternative medicine use by cancer patients. Med J Aust. 1996;165:545-8.

10. Miller M, Boyer MJ, Butow PN, Gattellari M, Dunn SM, Childs A. The use of unproven methods of treatment by cancer patients: frequency, expectations and cost. Support Care Cancer. 1998;6:337-47.

11. Chrystal K, Allan S, Forgenson G, Isaacs R. The use of complementary/alternative medicine by cancer patients in a New Zealand regional cancer treatment centre. N Z Med J. 2003;116(1168):U296.

12. Tascilar M, de Jong FA, Verweij J, Mathijssen RH. Complementary and alternative medicine during cancer treatment: beyond innocence. Oncologist. 2006;11:732-41.

13. Xue CCL, Zhang AL, Lin V, Da Coast C, Story DF. Complementary and alternative medicine use in Australia: a national population-based survey. J Altern Complement Med. 2007;13:643-50.

14. Oh B, Butow P, Mullan B, Beale P, Pavlakis N, Rosenthal D et al. The use and perceived benefits results from the use of complementary and alternative medicine by cancer patients in Australia. Asia-Pac J Clin Onco. 2010;6:342-9.

15. Wong LC, Chan E, Tay S, Lee KM, Back M. Complementary and alternative medicine practices among Asian radiotherapy patients. Asia-Pac J Clin Onco. 2010;6:357-63.

16. Deng G, Cassileth B, Cohen L, Gubili J, Johnstone P, Kumar N et al. Integrative Oncology Practice Guidelines. J Soc Integrat Onc. 2007;5(2):65-84.

17. Weiger WA, Smith M, Boon H, Richardson MA, Kaptchuk TJ, Eisenberg DM. Advising patients who seek complementary and alternative medical therapies for cancer. Ann Intern Med. 2002;137:889-903.

18. Cancer Council Queensland [Internet]. Complementary and alternative therapies: making an informed decision. Queensland: The Association; 2006. [updated 2006; cited 2011 February 9]. Available from:http://www.cancerqld.org.au/icms_docs/60399_Complementary_and_alternative_therapies_making_an_informed_decision.pdf

19. Bauer JD, Ash S, Davidson WL, Hill JM, Brown T, Isenring EA, et al. Evidence based practice guidelines for the nutritional management of cancer cachexia. Nutrition & Dietetics. 2006;63:S3–S32.

20. National Health and Medical Research Council [Internet]. A guide to the development, implementation and evaluation of clinical practice guidelines. Canberra; Commonwealth of Australia; 1999. [endorsed 1998 November 16; cited 2011 February 9]. Available from: http://www.nhmrc.gov.au/_files_nhmrc/file/publications/synopses/cp30.pdf

21. Shuakat A, Scouras N, Schunemann HJ. Role of supplemental calcium in the recurrence of colorectal adenomas: a meta-analysis of randomised controlled trials. Am J Gastroenterol. 2005;100(2):390-4.

22. Weingarten MAMA, Zalmanovici A, Yaphe J. Dietary calcium supplementation for preventing colorectal cancer and adenomatous polyps. Cochrane Database of Systematic Reviews 2008, Issue I. Art. No.: CD003548. DOI: 10.1002/14651858.CD003548.pub4.

23. Greenlee H, Hershman DL, Jacobson JS. Use of antioxidant supplements during breast cancer treatment: a comprehensive review. Breast Cancer Res Tr. 2009;115(3):437-52.

24. Ernst E. Complementary and alternative therapies for cancer. Up-To-Date Reviews [Internet]. 2009 September 30 [cited 2010 February 11]. Available from: http://www.uptodate.com

25. Block KI, Koch AC, Mead MN, Tothy PD, Newman RA, Gyllenhaal C.  Impact of antioxidant supplementation on chemotherapeutic efficacy: a systematic review of the evidence from randomized controlled trials. Cancer Treat Rev. 2007;33:407-18.

26. Block KI, Koch AC, Mead MN, Tothy PD, Newman RA, Gyllenhaal C.  Impact of antioxidant supplementation on chemotherapeutic toxicity: a systematic review of the evidence from randomized controlled trials. Int J Cancer. 2008;123:1227-39.

27. Sood A, Barton DL, Bauer BA, Loprinzi CL. A critical review of complementary therapies for cancer-related fatigue. Integrative Cancer Therapies. 2007;6(1):8-13.

28. Doyle C, Kushi L, Byers T, Courneya K, Demark-Wahnefried W, Grant B, et al. The 2006 Nutrition, Physical Activity and Cancer Survivorship Advisory Committee, American Cancer Society. Nutrition and physical activity during and after cancer treatment: an American Cancer Society guide for informed choices. CA-Cancer J Clin. 2006 Nov-Dec;56 (6):323-53.

29. American Dietetic Association (ADA). Oncology evidence-based nutrition practice guideline. Chicago: The Association; 2007 Oct:various p.

30. Lawenda BD, Delly KM, Ladas, EJ, Sagar SM, Vickers A, Blumberg JB. Should supplemental antioxidant administration be avoided during chemotherapy and radiation therapy? J Natl Cancer I. 2008;100:773-83.

31. Gray J, Mao J, Szabo E, Kelley M, Kurie J, Bepler G; American College of Chest Physicians. Lung cancer chemoprevention: ACCP evidence-based clinical practice guidelines (2nd edition). Chest. 2007 Sep;132 (3 suppl):56S-68S.

32. McGough C, Baldwin C, Frost G, Andreyev HJ. Role of nutritional intervention in patients treated with radiotherapy for pelvic malignancy. Brit J Cancer. 2004;90(12):2278-87.

33. Veronesi U, De Palo G, Marubini E, Coasta A, Formelli F, Mariani L, et al for the Fenretinide Trial Investigators. Randomised Trial of Fenretinide to Prevent Second Breast Malignancy in Women with Early Breast Cancer. J Natl Cancer I. 1999;91:1847-56.

34. Gerber B, Scholz C, Reimer T, Briese V, Janni W. Complementary and alternative therapeutic approaches in patients with early breast cancer: a systematic review. Breast Cancer Res Tr. 2006;95:199-209.

35. Nakachi K, Suemasu K, Suga K, Takeo T, Imai K, Higashi Y. Influence of drinking green tea on breast cancer malignancy among Japanese patients. Jpn J Cancer Res.1998; 89:254-61 cited in Fujiki H. Two stages of cancer prevention with green tea. J Cancer Res Clin. 1999; 125: 589-97.

36. Boehm K, Borrelli F, Ernst E, Habacher G, Hung SK, Milazzo S, et al. Green tea (Camellia sinensis) for the prevention of cancer. Cochrane Database of Systematic Reviews 2009, Issue 3. Art. No: CD005004. DOI:10.1002/14651858.CD005004.pub2.

37. Horneber MA, Bueschel G, Huber R, Linde K, Rostock M. Mistletoe therapy in oncology. Cochrane Database of Systematic Reviews 2008, Issue 2. Art. No.: CD003297. DOI: 10.1002/14651858.CD003297.pub2.

38. Kienle GS, Kiene H. Complementary cancer therapy: a systematic review of prospective clinical trials on anthroposophic mistletoe extracts. Eur J Med Res. 2007;12(3):103-19.

39. Zhang M, Liu X, Li J, He L, Tripathy D. Chinese medicinal herbs to treat the side effects of chemotherapy in breast cancer patients. Cochrane Database of Systematic Reviews 2007, Issue 2. Art. No.: CD004921.DOI: 10.1002/14651858.CD004921.pub2.

40. Gan T, Wu Z, Tian L, Wang Y. Chinese herbal medicines for induction of remission in advanced or late gastric cancer. Cochrane Database of Systematic Reviews 2010, Issue 1. Art.No.: CD005096. DOI: 10.1002/14651858.CD005096.pub2.

41. Sparreboom A, Cox MC, Acharya MR, Figg WD. Herbal remedies in the United States: Potential Adverse Interactions with Anticancer Agents. J Clin Oncol, 2004;22(12):2489-2503.

42. Moyad M. Osteoporosis – Part II: Dietary and/or Supplemental Calcium and Vitamin D. Urol Nurs. 2002;22(6):405-9.

43. Van Veldhuizen PJ, Taylor SA, Williamson S, Drees BM. Treatment of Vitamin D Deficiency in Patients with Metastatic Prostate Cancer May Improve Bone Pain and Muscle Strength. J Urology. 2000;163:187-90.

44. Gross C, Stamley R, Hancock S, Feldman D. Treatment of Early Recurrent Prostate Cancer with 1,25-Dihydroxyvitamin D3 (calcitriol). J Urology. 1998;159(6):2035-9.

45. Wu T, Munro AJ, Guanjian L, Liu GJ. Chinese medical herbs for chemotherapy side effects in colorectal cancer patients. Cochrane Database of Systematic Reviews 2005, Issue 1. Art. No.: CD004540. DIO: 10.1002/14651858.CD004540.pub2.

46. Bardia A, Barton DL, Prokop LJ, Bauer BA, Moynihan TJ. Efficacy of complementary and alternative medicine therapies in relieving cancer pain: a systematic review. J Clin Oncol. 2006;24(34):5457-64.

47. Cassileth B, Deng G, Gomez J, Johnstone P, Kumar N, Vickers A; American College of Chest Physicians. Complementary therapies and integrative oncology in lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition). Chest. 2007 Sep;132(Suppl 3):340S-54S.

48 Dennert G, Horneber M. Selenium for alleviating the side effects of chemotherapy, radiotherapy and surgery in cancer patients. Cochrane Database of Systematic Reviews 2006, Issue 3. Art. No.: CD005037.DOI:10.1002/14651858.CD005037.pub2.

49. Haseen F, Cantwell MM, O’Sullivan JM, Murray LJ. Is there a benefit from lycopene supplementation in men with prostate cancer? A systematic review. Prostate Cancer P D. 2009;12(4):325-32.

50. World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. Washington DC: The Association; 2007.

51. Myung SK, Kim Y, Ju W, Choi HJ, Bae WK. Effects of antioxidant supplements on cancer prevention: meta-analysis of randomized controlled trials. Ann Oncol. 2010;21(1):166-79.

52. Bjekakovic G, Nikolova D, Simonetti RG, Gluud C. Systematic review: primary and secondary prevention of gastrointestinal cancers with antioxidant supplements. Aliment Pharm Therap. 2008;28(6):689-703.

53. Davies AA, Davey Smith G, Harbord R, Bekkering GE, Sterne JA, Beynon R et al. Nutritional interventions and outcome in patients with cancer or preinvasive lesions: systematic review. J Natl Cancer I. 2006;98(14):961-73.

54. Milazzo S, Ernst E, Lejeune S, Schmidt K. Laetrile treatment for cancer. Cochrane Database of Systematic Reviews 2006, Issue 2. Art. No.: CD005476. DOI: 10.1002/14651858.CD005476.pub2.

55. Natural Medicines Comprehensive Database [Internet]. Stockton: Therapeutic Research Faculty; c1995-2011 [cited 2011 February 11]. Available from: http://www.naturaldatabase.com

56. Memorial Sloan-Kettering Cancer Center [Internet]. New York: The Centre; c2011 [cited 2011 February 11]. About herbs, botanicals, and other products; Available from: http://www.mskcc.org/mskcc/html/11570.cfm

57. National Center for Complementary and Alternative Medicine [Internet].  Maryland: National Institutes of Health [cited 2011 February 11]. Available from: www.nccam.nih.gov.

58. Office of Cancer Complementary and Alternative Medicine [Internet]. Maryland: National Institutes of Health [cited 2011 February 11]. CAM therapies: A-Z. Available from: http://www.cancer.gov/cam/health_camaz.html

59. Therapeutic Goods Administration [Internet]. Woden: Department of Health and Ageing [cited 2011 February 11]. Australian register of therapeutic goods; Available from: http://www.tga.gov.au/docs/html/artg.htm

60. Australian Health Ministers’ Advisory Council [Internet]. Canberra: Australia’s Health Workforce Online [cited 2011 March 4]. Preparing to incorporate four further health professions into NRAS; Available from: http://www.nras2012.ahpra.gov.au

61. SolarisCare [Internet]. Nedlands: The Foundation [cited 2011 February 11]. Available from: http://solariscare.org.au/home/

62. Joske D, Petterson A, Philips M. Complementary therapies for cancer patients: eight years’ experience in a W.A. teaching hospital. In: Australia and New Zealand Head and Neck Society 11th Annual Scientific Meeting: Program and Abstracts; 2009 Aug 6-8, Fremantle, Western Australia, p. 23.

Be the first to know when a new issue is online. Subscribe today.