Complementary and alternative medicine is a group of diverse medical and health care systems, practices, and products that are not presently considered to be part of conventional medicine. Conventional medicine is medicine as practiced by holders of M.D. (medical doctor) or D.O. (doctor of osteopathy) degrees and by their allied health professionals, such as physical therapists, psychologists, and registered nurses. Some health care providers practice both CAM and conventional medicine.
This fact sheet answers some frequently asked questions about the use of CAM therapies and the way that CAM approaches are evaluated. To find out more about topics and resources mentioned in this fact sheet, see " For More Information ."
According to a comprehensive survey on Americans' use of CAM, 36 percent of U.S. adults are using some form of CAM. When megavitamin therapy and prayer for health reasons are included in the definition of CAM, that percentage rises to 62 percent. These results are based on the 2002 National Health Interview Survey, which was supported by NCCAM and the National Center for Health Statistics (part of the Centers for Disease Control and Prevention). The survey found that rates of CAM use are especially high among patients with serious illnesses such as cancer.
Several smaller studies of CAM use by cancer patients have been conducted. A study of CAM use in patients with cancer in the July 2000 issue of the Journal of Clinical Oncology found that 69 percent of 453 cancer patients had used at least one CAM therapy as part of their cancer treatment. A study published in the December 2004 issue of the Journal of Clinical Oncology reported that 88 percent of 102 people with cancer who were enrolled in phase I clinical trials (research studies in people) at the Mayo Comprehensive Cancer Center had used at least one CAM therapy. Of those, 93 percent had used supplements (such as vitamins or minerals), 53 percent had used nonsupplement forms of CAM (such as prayer/spiritual practices or chiropractic care), and almost 47 percent had used both.
A review article in the March 2005 issue of the Southern Medical Journal reported that cancer patients take supplements to reduce side effects and organ toxicity, to protect and stimulate their immune systems, or to prevent further cancers or recurrences. Patients frequently see using supplements as a way to take control over their health and increase their quality of life.
Additional information about CAM use among cancer patients can be found in a review article published in Seminars in Oncology in December 2002.
The same rigorous scientific evaluation used to assess conventional cancer treatments should be used for CAM therapies. NCCAM is funding a number of clinical trials to evaluate CAM therapies for cancer.
Conventional cancer treatments are studied for safety and effectiveness through a rigorous scientific process that includes laboratory research and clinical trials with large numbers of patients. Less is known about the safety and effectiveness of complementary and alternative methods to treat cancer, although some CAM therapies have undergone rigorous evaluation.
A small number of CAM therapies, which were originally considered to be purely alternative approaches, are finding a place in cancer treatment--not as cures, but as complementary therapies that may help patients feel better and recover faster. One example is acupuncture --family of procedures that originated in traditional Chinese medicine. Acupuncture is the stimulation of specific points on the body by a variety of techniques, including the insertion of thin metal needles though the skin. It is intended to remove blockages in the flow of qi and restore and maintain health. . In 1997, a panel of experts at the National Institutes of Health (NIH) Consensus Conference found acupuncture to be effective in managing chemotherapy-associated nausea and vomiting and in controlling pain associated with surgery. In contrast, some approaches, such as the use of laetrile, have been studied and found ineffective or potentially harmful.
NCCAM is sponsoring a number of clinical trials to study complementary and alternative treatments for cancer. Some of these trials study the effects of complementary approaches used in addition to conventional treatments, while others compare alternative therapies with conventional treatments. Recent trials include the following:
Patients who are interested in taking part in these or any other clinical trials should talk with their health care provider.
Patients, family members, and health professionals can use the following Web resources to find out about CAM clinical trials:
Cancer patients who are using or considering CAM should discuss this decision with their health care provider, as they would any therapy. Some complementary and alternative therapies may interfere with standard treatment or may be harmful when used along with standard treatment. The booklet "Thinking About Complementary and Alternative Medicine: A Guide for People with Cancer" discusses choices that people face in making decisions about cancer treatment and includes suggestions on how to talk with health care providers about these choices.
As with any medicine or treatment, it is a good idea to learn about the therapy, including whether the results of scientific studies support the claims that are made for it.
These fact sheets contain further information on evaluating CAM therapies, selecting practitioners, and considering financial issues for CAM treatment:
Barnes PM, Powell-Griner E, McFann K, Nahin RL. Complementary and alternative medicine use among adults: United States, 2002 . CDC Advance Data Report #343. 2004.
Dy GK, Bekele L, Hanson LJ, et al. Complementary and alternative medicine use by patients enrolled onto phase I clinical trials . Journal of Clinical Oncology . 2004;22(23):4810-4815.
Frenkel M, Ben-Arye E, Baldwin C, et al. Approach to communicating with patients about the use of nutritional supplements in cancer care . Southern Medical Journal . 2005;98(3):289-294.
National Cancer Institute. PDQ Cancer Information Summary: Laetrile/Amygdalin . National Cancer Institute Web site. Accessed on August 11, 2005.
National Institutes of Health. Acupuncture: NIH Consensus Statement . National Institutes of Health Office of Disease Prevention Web site. Accessed on August 30, 2005.
Richardson MA, Sanders T, Palmer JL, et al. Complementary/alternative medicine use in a comprehensive cancer center and the implications for oncology . Journal of Clinical Oncology. 2000;18(13):2505-2514.
Richardson MA, Straus SE. Complementary and alternative medicine: opportunities and challenges for cancer management and research . Seminars in Oncology . 2002;29(6):531-545.
Sparber A, Wooton JC. Surveys of complementary and alternative medicine: Part II. Use of alternative and complementary cancer therapies . Journal of Alternative and Complementary Medicine . 2001;7(3):281-287.
The NCCAM Clearinghouse provides information on CAM and NCCAM, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.
National Cancer Institute's Cancer Information Service
The National Cancer Institute (NCI) is the lead Federal Government agency for cancer research. NCI's Cancer Information Service can provide answers to questions about cancer, help with quitting smoking, informational materials, and help in using the NCI Web site.
A service of the National Library of Medicine (NLM), PubMed contains publication information and (in most cases) brief summaries of articles from scientific and medical journals. CAM on PubMed, developed jointly by NCCAM and NLM, is a subset of the PubMed system and focuses on the topic of CAM.
NCCAM has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your primary health care provider. We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCAM.