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Complementary and Alternative Medicine

Photo collage of cups of green tea, woman receives a massage, acupuncture is given, and man practices tai chi.

Complementary and alternative medicine includes practices such as massage, acupuncture, tai chi, and drinking green tea.

Credit: iStock

Complementary and alternative medicine (CAM) is the term for medical products and practices that are not part of standard medical care. People with cancer may use CAM to

  • help cope with the side effects of cancer treatments, such as nausea, pain, and fatigue
  • comfort themselves and ease the worries of cancer treatment and related stress
  • feel that they are doing something to help with their own care
  • try to treat or cure their cancer

Integrative medicine is an approach to medical care that combines conventional medicine with CAM practices that have shown through science to be safe and effective. This approach often stresses the patient's preferences, and it attempts to address the mental, physical, and spiritual aspects of health.

Conventional medicine is a system in which health professionals who hold an M.D. (medical doctor) or D.O. (doctor of osteopathy) degree treat symptoms and diseases using drugs, radiation, or surgery.  It is also practiced by other health professionals, such as nurses, pharmacists, physician assistants, and therapists. It may also be called allopathic medicinebiomedicine, Western, mainstream, or orthodox medicine. Some conventional medical care practitioners are also practitioners of CAM.

Standard medical care is treatment that is accepted by medical experts as a proper treatment for a certain type of disease and that is widely used by healthcare professionals. Also called best practice, standard of care, and standard therapy.

Complementary medicine is used along with standard medical treatment but is not considered by itself to be standard treatment. One example is using acupuncture to help lessen some side effects of cancer treatment. Less research has been done for most types of complementary medicine.

Alternative medicine is used instead of standard medical treatment. One example is using a special diet to treat cancer instead of cancer drugs that are prescribed by an oncologist. Less research has been done for most types of alternative medicine. 

Types of Complementary and Alternative Medicine

Scientists learn about CAM therapies every day, but there is still more to learn. This list is meant to be an introduction to what types of CAM are practiced, not an endorsement. Some of the therapies listed below still need more research to prove that they can be helpful. If you have cancer, you should discuss your thoughts about using CAM with your health care provider before using the therapies listed below. 

People may use the term "natural," "holistic," "home remedy," or "Eastern Medicine" to refer to CAM. However, experts often use five categories to describe it. These are listed below with examples for each. 

Mind–body therapies

These combine mental focus, breathing, and body movements to help relax the body and mind. Some examples are

  • meditation: focused breathing or repetition of words or phrases to quiet the mind and lessen stressful thoughts and feelings.
  • biofeedback: using special machines, the patient learns how to control certain body functions that are normally out of one's awareness (such as heart rate and blood pressure).
  • hypnosis: a trance-like state in which a person becomes more aware and focused on certain feelings, thoughts, images, sensations or behaviors. A person may feel more calm and open to suggestion in order to aid in healing.
  • yoga: ancient system of practices used to balance the mind and body through stretches and poses, meditation, and controlled breathing
  • tai chi: a form of gentle exercise and meditation that uses slow sets of body movements and controlled breathing
  • imagery:  focusing on positive images in the mind, such as imagining scenes, pictures, or experiences to help the body heal
  • creative outlets: interests such as art, music, or dance

Biologically based practices

This type of CAM uses things found in nature. Some examples are

Manipulative and body-based practices

These are based on working with one or more parts of the body. Some examples are

  • massage therapy: a therapy where the soft tissues of the body are kneaded, rubbed, tapped, and stroked
  • chiropractic therapy: a type of manipulation of the spine, joints, and skeletal system
  • reflexology: a type of massage in which pressure is applied to specific points on the feet or hands, which are believed to match up with certain parts of the body

Energy healing

Energy healing is based on the belief that a vital energy flows through the body. The goal is to balance the energy flow in the patient. There's not enough evidence to support the existence of energy fields. However, there are no harmful effects in using these approaches. Some examples are

  • reiki: placing hands lightly on or just above the person with the goal of guiding energy to help a person's own healing response
  • therapeutic touch: moving hands over energy fields of the body or gently touching a person's body

Whole medical systems

These are healing systems and beliefs that have evolved over time in different cultures and parts of the world. Some examples are

  • Ayurvedic medicine: a system from India in which the goal is to cleanse the body and restore balance to the body, mind, and spirit. It uses diet, herbal medicines, exercise, meditation, breathing, physical therapy, and other methods.
  • Traditional Chinese medicine: based on the belief that qi (the body’s vital energy) flows along meridians (channels) in the body and keeps a person’s spiritual, emotional, mental, and physical health in balance. It aims to restore the body’s balance between two forces called yin and yang.
    • Acupuncture is a common practice in Chinese medicine that involves stimulating certain points on the body to promote health, or to lessen disease symptoms and treatment side effects.
  • naturopathic medicine: a system that avoids drugs and surgery. It is based on the use of natural agents such as air, water, light, heat and massage to help the body heal itself. It may also use herbal products, nutrition, acupuncture, and aromatherapy.

For details about specific CAM therapies, NCI provides evidence-based Physician Data Query (PDQ) information for many CAM therapies in versions for both the patient and health professional.  Also see the page from the National Center for Complementary and Integrative Health (NCCIH) Cancer and Complementary Health Approaches: What You Need to Know for more details about CAM and some of the current research. 

The Safety of CAM

Some CAM therapies have undergone careful evaluation and have been found to be generally safe and effective. These include acupuncture, yoga, and meditation to name a few. However, there are others that do not work, may be harmful, or could interact negatively with your medicines.

Natural does not mean safe

CAM therapies include a wide variety of botanicals and nutritional products, such as herbal and dietary supplements, and vitamins. These products do not have to be approved by the Food and Drug Administration (FDA) before being sold to the public. Also, a prescription isn't needed to buy them. Therefore, it's up to you to decide what's best for you. Some tips to keep in mind are below.

  • Herbal supplements may be harmful when taken by themselves, with other substances, or in large doses. For example, some studies have shown that kava kava, an herb that has been used to help with stress and anxiety, may cause liver damage. And St. John, which some people use for depression, may cause certain cancer drugs to not work as well as they should.
  • Tell your doctor if you're taking any dietary supplements, even vitamins, no matter how safe you think they are. This is very important. Even though there may be ads or claims that something has been used for years, they do not prove that it's safe or effective. This is even more true when combined with your medicines.

Diet alone cannot control cancer

It's common for people with cancer to have questions about different foods to eat during treatment. Yet it's important to know there isn't just one food or special diet that has proved to control cancer. 

  • We all have different bodies and ways we metabolize food. What is best for someone else may not be right for you. Because of your individual nutrition needs, it’s best to talk with the doctor in charge of your treatment about the foods you should be eating.
  • It's always important for you to have a healthy diet, but especially now. Do the best you can to have a well-rounded approach, eating a variety of foods that are good for you. For advice about eating during and after cancer treatment, see the NCI booklet, Eating Hints.

It’s important to know that there are no studies that prove that any special diet, food, vitamin, mineral, dietary supplement, herb, or combination of these can slow cancer, cure it, or keep it from coming back. In fact, some of these products can cause other problems by changing how your cancer treatment works.

Talk with your doctor before you use CAM

Cancer patients who want to use CAM should talk with their doctor or nurse. This is an important step because things that seem safe could be harmful or even interfere with your cancer treatment. It's also a good idea to learn if the therapy you're thinking about has been proven to do what it claims to do. Some examples of questions to ask:

What types of CAM therapies might help me

  • reduce my stress and anxiety?
  • feel less tired?
  • deal with cancer symptoms and side effects, such as pain or nausea?
  • sleep better?

Always tell your doctor about what complementary health approaches you’re using. Whether it's something that seems simple, such as massage or a type of exercise, it's good to let your doctor or nurse know what you're doing. Don’t forget to tell them about over-the-counter and prescription medicines that you're taking. Make a list in advance and take it with you.

Don't be afraid to ask questions. It's okay to feel hesitant when asking about using CAM. But doctors want to know what concerns you have so they can give you the best possible care. Let them know that you would like to use CAM methods and want their input.

Questions to ask a CAM practitioner

Choosing a CAM practitioner should be done with the same care as choosing a doctor. Ask your doctor, nurse, or social worker at your cancer center to help you find a practitioner for you. For more tips to help you in your search, see 6 Things to Know When Selecting a Complementary Health Practitioner from NCCIH. Once you choose someone to see, questions you may want to ask include:

  • What types of CAM do you practice?
  • What are your training and qualifications?
  • Do you see other patients with my type of cancer?
  • Will you work with my doctor if necessary?

Questions to ask about the CAM therapy 

  • How can this help me? 
  • Do you know of studies that prove it helps?
  • What are the risks and side effects?
  • Will this interfere with my cancer treatment?
  • How long will I be on the therapy? 
  • What will it cost? Do you take insurance?
  • Do you have information that I can read about it?

Questions to ask yourself about the CAM practitioner

  • Do I feel comfortable with this person?
  • Do I like how the office looks and feels?
  • Do I like the staff?
  • Does this person support standard cancer treatments?
  • How far am I willing to travel for treatment?
  • Is it easy to get an appointment? 
  • Are the office hours good for me?
  • Will insurance cover my costs? (Call your health plan or insurer to see whether they cover CAM therapies. Many are not covered.)

Clinical Trials to Test CAM Therapies

NCI and the National Center for Complementary and Integrative Health (NCCIH) are currently sponsoring or cosponsoring clinical trials that test CAM treatments and therapies in people. Some study the effects of complementary approaches used in addition to conventional treatments, and some compare alternative therapies with conventional treatments. You can find a list of all cancer CAM clinical trials here.

Lifelines: Complementary and Alternative Medicine

Dr. Jeffrey D. White, OCCAM Director, explains the use of complementary and alternative medicine in cancer.

Patients, their families, and their health care providers can learn about CAM therapies and practitioners from the following government agencies: