Complementary and alternative medicine (CAM) has been in the mainstream of healthcare for thousands of years in China, and in India where Ayurveda has long been practiced as a holistic approach to health, based on maintaining balance in body, mind, and consciousness through proper diet and lifestyle, as well as herbal remedies.
Now, in the United States, a growing proportion of cancer patients and cancer survivors are adopting CAM diets and taking herbs, vitamins, and supplements for their healing properties—not in place of standard cancer therapy, but along with it and beyond treatment.
In this setting, research shows, the hope and promise of CAM nutrition comes with varying degrees of supportive evidence. But CAM and the concept of integrative care has joined the elite among medical research areas with a special unit within the National Institutes of Health: the National Center for Complementary and Alternative Medicine (NCCAM [http://nccam.nih.gov/
As much as 44% of all cancer survivors use CAM therapies, according to findings from a study by Judith Fouladbakhsh, PhD, APRN, and colleagues. Fouladbakhsh, associate professor at Wayne State University College of Nursing, and Liana Wheatley, BA, RN, OCN, a medical oncology nurse from Texas Oncology, reviewed the potential benefits and risks of CAM diets and nutritional supplements for cancer and other wellness goals at ONS 2013.
Anticancer diets, although they differ in guiding philosophies, use of specific supplements, food preparation (if any), and other particulars, typically share certain features. Most recommend high levels of antioxidants and phytochemicals, which are biologically active compounds found in plant-based foods such as fruits, vegetables, beans, and grains. Thousands of phytochemicals have been identified, but only a small fraction has received close scientific examination and verification of health benefits. Better known among the scientifically validated compounds are beta carotene and other carotenoids, ascorbic acid (vitamin C), folic acid, and vitamin E.
Also common among anticancer and other CAM diets is a recommendation for plant-based (vs animal-sourced) protein as well as fiber, omega-3 and omega-6 fatty acids and oils, minerals, and polyphenols, which are found in green tea, and curcumin (the major component of turmeric). Among a number of CAM diets discussed by Fouladbakhsh and Wheatley in their ONS overview, certain ones are labeled as “anticancer” diets, including the Dr. Oz Anti-Cancer Diet, Dr. Moerman’s Anti-Cancer Diet, The Maker’s Diet, and the Paleo Diet.
Herbs have been used for thousands of years as a form of healthcare, and evidence is accumulating in support of the potential of some to affect cancer risk and progression at the cellular level. Examples include resveratrol, a phytonutrient found in grapes (and red wine), cranberries, blueberries, and other foods; ginseng, which contains saponins, which possess antitumor effects, such as antiangiogenesis; ginkgo biloba, for its gene-regulatory and anti-angiogenic properties; lycopene (found in tomatoes), which may affect cancer risk; and green tea, which contains polyphenols and catechins that can inhibit cancer cell growth and proliferation.
Integrative medicine and incorporating standard medicine with CAM is “where it’s all going,” according to some nursing professionals. But there are also risks, especially to cancer patients. As NCCAM points out, these include evidence for interference with some standard cancer treatments.
Experts agree that the research basis for CAM diets and supplements is still inconclusive and that more extensive, randomized clinical trials are needed (Leuk Lymphoma
. 2010;51(8):1414-1423). Clinical practice guidelines for integrative oncology (J Soc Integr Oncol.
2009;7(3):85-120) make these cautions specific, saying that, based on a review of the literature, “…specific dietary supplements are not recommended for cancer prevention” and that providers should evaluate a patient’s use of dietary supplements prior to the start of therapy to assess for possible side effects and interactions.