Questions and Answers About Using Magnets to Treat Pain
Magnets are objects that produce a type of energy called magnetic fields. Magnets are widely marketed to treat or ease the symptoms of various diseases and conditions, including pain. This Research Report provides an overview of the use of magnets for pain, summarizes current scientific knowledge about their effectiveness for this purpose, and suggests additional sources of information. Terms are defined in the "Definitions" section.
The vast majority of magnets marketed to consumers to treat pain are of a type called static (or permanent) magnets, because the resulting magnetic fields are unchanging. The other magnets used for health purposes are called electromagnets, because they generate magnetic fields only when electrical current flows through them. Currently, electromagnets are used primarily under the supervision of a health care provider or in clinical trials.
Scientific research so far does not firmly support a conclusion that magnets of any type can relieve pain. However, some people do experience some relief. Various theories have been proposed as to why, but none has been scientifically proven (see Question 5).
Clinical trials in this area have produced conflicting results (see Question 8). Many concerns exist regarding the quality and rigor of the studies conducted to date, leading to a call for additional, higher quality, and larger studies.
The U.S. Food and Drug Administration (FDA) has not approved the marketing of magnets with claims of benefits to health (such as "relieves arthritis pain"). The FDA and the Federal Trade Commission (FTC) have taken action against many manufacturers, distributors, and Web sites that make claims not supported scientifically about the health benefits of magnets.
It is important that people inform their health care providers about any therapy they are currently using or considering, including magnets. This is to help ensure a safe and coordinated course of care.
1. What are magnets?
Magnets are objects that produce a type of energy called magnetic fields. All magnets possess a property called polarity--that is, a magnet's power of attraction is strongest at its opposite ends, usually called the north and south poles. The north and south poles attract each other, but north repels north and south repels south. All magnets attract iron.
Magnets come in different strengths, most often measured in units called gauss (G). For comparison purposes, the Earth has a magnetic field of about 0.5 G; refrigerator magnets range from 35 to 200 G; magnets marketed for the treatment of pain are usually 300 to 5,000 G; and MRI (magnetic resonance imaging) machines widely used to diagnose medical conditions noninvasively produce up to 200,000 G.1
The vast majority of magnets marketed to consumers for health purposes (see the box below) are of a type called static (or permanent) magnets. They have magnetic fields that do not change.
Examples of Products Using Magnets
Pillows and cushions
Bracelets and other jewelry
The other magnets used for health purposes are called electromagnets, because they generate magnetic fields only when electrical current flows through them. The magnetic field is created by passing an electric current through a wire coil wrapped around a magnetic core. Electromagnets can be pulsed--that is, the magnetic field is turned on and off very rapidly.
2. Is the use of magnets considered conventional medicine or complementary and alternative medicine?
Conventional medicine and complementary and alternative medicine (CAM) are defined in below.
About CAM and Conventional Medicine
Complementary and alternative medicine (CAM) is a group of various 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 allied health professionals, such as physical therapists, psychologists, and registered nurses.
There are some uses of electromagnets within conventional medicine. For example, scientists have found that electromagnets can be used to speed the healing of bone fractures that are not healing well.2,3 Even more commonly, electromagnets are used to map areas of the brain. However, most uses of magnets by consumers in attempts to treat pain are considered CAM, because they have not been scientifically proven and are not part of the practice of conventional medicine.
3. What is the history of the discovery and use of magnets to treat pain?
Magnets have been used for many centuries in attempts to treat pain.a By various accounts, this use began when people first noticed the presence of naturally magnetized stones, also called lodestones. Other accounts trace the beginning to a shepherd noticing that the nails in his sandals were pulled out by some stones. By the third century A.D., Greek physicians were using rings made of magnetized metal to treat arthritis and pills made of magnetized amber to stop bleeding. In the Middle Ages, doctors used magnets to treat gout, arthritis, poisoning, and baldness; to probe and clean wounds; and to retrieve arrowheads and other iron-containing objects from the body.
In the United States, magnetic devices (such as hairbrushes and insoles), magnetic salves, and clothes with magnets applied came into wide use after the Civil War, especially in some rural areas where few doctors were available. Healers claimed that magnetic fields existed in the blood, organs, or elsewhere in the body and that people became ill when their magnetic fields were depleted. Thus, healers marketed magnets as a means of "restoring" these magnetic fields. Magnets were promoted as cures for paralysis, asthma, seizures, blindness, cancer, and other conditions. The use of magnets to treat medical problems remained popular well into the 20th century. More recently, magnets have been marketed for a wide range of diseases and conditions, including pain, respiratory problems, high blood pressure, circulatory problems, arthritis, rheumatism, and stress.
*Sources for this historical discussion include references 1, 4, and 5.
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 in this information is not an endorsement by NCCAM.
National Center for Complementary and Alternative Medicine (NCCAM)
National Institutes of Health
Bethesda, Maryland 20892 USA
NCCAM Publication No. D208