National Center for Complementary and Integrative Health (NCCIH)

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Are You Considering Complementary Health Approaches?

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Millions of Americans use some form of complementary health approach. Like any decision concerning your health, decisions about whether to use complementary therapies are important. The National Center for Complementary and Integrative Health (NCCIH) has developed this fact sheet to assist you in your decisionmaking about complementary practices and products.

Key Points


What Do “Complementary,” “Integrative,” and “Alternative” Mean?

The term complementary medicine refers to a group of diverse medical and health care systems, practices, and products that are not generally considered to be part of conventional medicineMedicine 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. . Complementary medicine includes natural products, such as dietary supplements, herbs, and probioticsLive bacteria (and sometimes yeasts) found in foods such as yogurt or in dietary supplements. , as well as mind and body practices, such as meditationA conscious mental process using certain techniques—such as focusing attention or maintaining a specific posture—to suspend the stream of thoughts and relax the body and mind. , chiropractic, acupuncture, and massagePressing, rubbing, and moving muscles and other soft tissues of the body, primarily by using the hands and fingers. The aim is to increase the flow of blood and oxygen to the massaged area. .

Another term often used in discussions of therapies that are not part of conventional medicine is integrative medicineAn approach to medicine that combines treatments from conventional medicine and complementary medicine for which there is some high-quality scientific evidence of safety and effectiveness. . Integrative medicine combines conventional and complementary approaches in a coordinated way.

A third term, alternative medicine, refers to the use of approaches that are not part of conventional medicine as replacements for, rather than complements to, conventional treatment. NCCIH advises against using any product or practice that has not been proven safe and effective as a substitute for conventional medical treatment or as a reason to postpone seeing a doctor about any health problem. In some instances, stopping—or not starting—conventional treatment can have serious consequences. Before making a decision not to use a proven conventional treatment, talk to your health care providers.


How can I get reliable information about a complementary therapy?

It is important to learn what scientific studies have discovered about the therapy you are considering. Making a decision based on the facts is a better idea than using a therapy simply because of something you have seen in an advertisement or on a Web site or because someone has told you that it worked for them. (For tips on how to evaluate Web site information, see the NCCIH fact sheet Evaluating Web-Based Health Resources.)

Understanding a therapy’s potential benefits, risks, and scientific evidence is critical to your health and safety. Scientific research on many complementary therapies is relatively new, so this kind of information may not be available for every therapy. However, many studies are under way, including those that NCCIH supports, and knowledge and understanding of complementary therapies are increasing all the time. Here are some ways to find reliable information:

  • Talk with your health care providers. Tell them about the product or practice you are considering and ask any questions you may have about safety, effectiveness, or interactions with medications (prescription or nonprescription) or dietary supplements.
  • Visit the NCCIH Web site ( The “Health Information” page has information on specific complementary therapies and links to other online sources of information. The Web site also has contact information for the NCCIH Clearinghouse, where information specialists are available to assist you in searching the scientific literature and to suggest useful NCCIH publications. You can also find information from NCCIH on Facebook, Twitter, and YouTube.
  • Visit your local library or a medical library. Ask the reference librarian to help you find scientific journals and trustworthy books with information on the therapy that interests you.


About Scientific Evidence on Complementary Health Approaches

Scientific evidence on complementary health approaches includes results from laboratory research (e.g., animal studies) as well as clinical trials (studies in people). It encompasses both “positive” findings (evidence that an approach may work) and “negative” findings (evidence that it probably does not work or that it may be unsafe). Scientific journals publish study results as well as review articles that evaluate the evidence as it accumulates. NCCIH fact sheets on specific health conditions or complementary approaches base information about research findings primarily on the most rigorous review articles, known as systematic reviews and meta-analyses. Authors of such reviews often conclude that more research and/or better designed studies are needed.

Are complementary therapies safe? How can I minimize risks in using these therapies?

As with any medical product or treatment, there can be risks with complementary therapies. These risks depend on the specific therapy. Each therapy needs to be considered on its own. However, if you are considering a specific therapy, the following general suggestions can help you think about safety and minimize risks.

  • If you decide to use a dietary supplement, such as an herbal product, be aware that some products may interact with medications (prescription or over-the-counter) or other dietary supplements, and some may have side effects on their own. (To learn more, see the NCCIH fact sheet Using Dietary Supplements Wisely.)
  • Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care. For tips about talking with your health care providers about complementary health approaches, see NCCIH’s Time to talk campaign.


How can I determine whether statements made about the effectiveness of a complementary therapy are true?

Statements that manufacturers and providers of complementary therapies may make about effectiveness and benefits can sound reasonable and promising. However, the statements may not be based on scientific evidence. Before you begin using a complementary therapy, it is a good idea to ask the following questions:

  • Is there scientific evidence (not just personal stories) to back up the statements?
  • Does the Federal Government have anything to report about the therapy?
  • How does the provider or manufacturer describe the therapy?
    • Question terms like “scientific breakthrough,” “miracle cure,” “secret ingredient,” or “ancient remedy.”
    • If you encounter claims of a “quick fix” that depart from previous research, keep in mind that science usually advances over time by small steps, slowly building an evidence base.
    • Remember: if it sounds too good to be true—for example, claims that a therapy can cure a disease or works for a variety of ailments—it usually is.


Are complementary therapies tested to see if they work?

While scientific evidence exists regarding the effectiveness and safety of some complementary therapies, for most there are key questions that are yet to be answered through well-designed scientific studies—questions such as whether the therapies are safe, whether they work for the diseases or medical conditions for which they are used, and how those therapies with health benefits may work. As the Federal Government’s lead agency for scientific research on the diverse complementary medical and health care systems, practices, and products that are not generally considered part of conventional medicine, NCCIH supports studies to answer these questions and determine who might benefit most from the use of specific therapies.


I am interested in a therapy that involves treatment from a complementary health practitioner. How do I go about selecting a practitioner?

Your primary health care provider or local hospital may be able to recommend a complementary health practitioner. The professional organization for the type of practitioner you are seeking may have helpful information, such as licensing and training requirements. Many states have regulatory agencies or licensing boards for certain types of complementary health practitioners; they may be able to help you locate practitioners in your area. For more suggestions, see 6 Things To Know When Selecting a Complementary Health Practitioner and Credentialing: Understanding the Education, Training, Regulation, and Licensing of Complementary Health Practitioners.


Can I receive treatment or a referral to a complementary health practitioner from NCCIH?

NCCIH does not provide treatment or referrals to complementary health practitioners. NCCIH’s mission is to define, through rigorous scientific investigation, the usefulness and safety of complementary and integrative health interventions and their roles in improving health and health care.


Can I participate in a clinical trial of a complementary therapy?

NCCIH supports clinical trials on complementary therapies. These trials are taking place in many locations, and study participants are needed. To learn more or to find trials that are recruiting participants, visit NIH Clinical Research Trials and You. If you do not have access to the Internet, contact the NCCIH Clearinghouse for information.



For More Information

NCCIH Clearinghouse

The NCCIH Clearinghouse provides information on NCCIH and complementary health approaches, 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.

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Office of Dietary Supplements (ODS), National Institutes of Health (NIH)

ODS seeks to strengthen knowledge and understanding of dietary supplements by evaluating scientific information, supporting research, sharing research results, and educating the public. Its resources include publications (such as Dietary Supplements: What You Need to Know), fact sheets on a variety of specific supplement ingredients and products (such as vitamin D and multivitamin/mineral supplements), and the PubMed Dietary Supplement Subset.

PubMed Dietary Supplement Subset:

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NIH National Library of Medicine's MedlinePlus

To provide resources that help answer health questions, MedlinePlus brings together authoritative information from the National Institutes of Health as well as other Government agencies and health-related organizations.

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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.

U.S. Food and Drug Administration (FDA)

The FDA oversees the safety of many products, such as foods, medicines, dietary supplements, medical devices, and cosmetics. Its series of consumer updates includes the publication FDA 101: Dietary Supplements and Tips for Dietary Supplement Users.

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Federal Trade Commission (FTC)

The FTC is the Federal agency charged with protecting the public against unfair and deceptive business practices. A key area of its work is the regulation of advertising (except for prescription drugs and medical devices).

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This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCIH 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 NCCIH.

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NCCIH Pub No.: 
Date Created: 
Diciembre 2006
Last Updated: 
Marzo 2013