Growing numbers of Americans are using homeopathy, a 19th-century system of medicine that relies on highly diluted remedies to spur self-healing. Some hospitals are offering homeopathic treatments, and some health insurance plans now cover them. Despite tales of dramatic healing from some patients, skeptics say it is biologically impossible for homeopathy to work as believers claim. The medicines are so diluted that it's highly unlikely they retain any of the original active ingredients. But some randomized, controlled studies have found that homeopathy works better than a placebo for flu, allergies, postoperative constipation and childhood diarrhea. Patients' reports of miraculous cures remain a mystery, but some experts attribute them to the healing power of belief.

Sarah Glazer specializes in health, education and social-policy issues. Her articles have appeared in The Washington Post, Glamour, The Public Interest and Gender and Work, a book of essays. Glazer covered energy legislation for the Environmental and Energy Study Conference and reported for United Press International. She holds a BA in American history from the University of Chicago.