PEOPLE USE THE phrase “alternative medicine” to describe any number of healing methods—from Swedish massage to Chinese herbalism and from energy realignment to aromatherapy. But in recent years, these three practices have gained mainstream acceptance in the U.S. health market:

CHIROPRACTIC MEDICINE

Origins A self-taught healer in Iowa named Daniel David Palmer popularized modern chiropractic medicine in the 19th century. Palmer theorized that misaligned vertebrae would alter the flow of energy through the nervous system—and thus was the cause of disease.

Applications Any pains or strains affecting muscles, joints, bones and connective tissue.

Treatment methods The best-known technique is the “adjustment”—a sudden, controlled force to an injured tissue or joint that’s intended to restore lost mobility and allow tissues to heal. But not every visit to the chiropractor results in loud bone-cracking sounds. Depending on the ailment, a chiropractor may also employ deep-tissue massage and rhythmic stretches.

ACUPUNCTURE

Origins Acupuncture is but one aspect of traditional Chinese medicine, an ancient system that conceives of health as a balancing act between opposing forces of yin (passive principle) and yang (excited principle). Studies suggest that acupuncture may boost the body’s production of pain-killing endorphins and immune-system cells.

Applications Pain management, whether from arthritis or sciatica, as well as a wide range of maladies, from allergies to addictions to infertility.

Treatment methods After identifying blocked qi (or “life-force”) pathways, the acupuncturist inserts slender needles (from a handful to 20 or more) about ¼ inch to 1½ inch into the skin. In most cases, patients relax for 30 minutes or more on a treatment table with the needles in place.

NATUROPATHY

Origins Rooted in healing practices originally developed in European spas, naturopathy arrived in the United States at the turn of the 20th century by way of a German-born immigrant, Benedict Lust, who founded the American Naturopathic Association in New York City.

Applications Any sickness that a family physician would treat, from menstrual irregularity to back pain.

Treatment methods Naturopathic physicians aim to address the root cause of disease, often dispensing lifestyle advice (cut back on caffeine to ease frayed nerves) rather than prescribing drugs and surgeries. Other treatments can include vitamin and mineral supplements, diet plans and hydrotherapy (applying hot and cold water to, say, decrease inflammation from a pulled muscle).