Since it was introduced first in the late 18th century, homeopathy has been appreciated by some of world's most famous and respected individuals. Dr. Oz talks with Dana Ullman, author of The Homeopathic Revolution: Why Famous People and Cultural Heroes Choose Homeopathy, about the basic principles behind this alternative form of medicine.

Homeopathic remedies are made from substances that, in undiluted form and in very small doses, cause symptoms similar to the disease or illness they aim to treat. "We find a medicine in nature that will mimic the symptoms of the body, that will mimic what efforts the body is trying to heal itself," Dana says. For example, he says homeopathic doses of arsenic can be used to treat the food poisoning-type symptoms caused by an arsenic overdose.

While this logic is often cited as contradictory—and controversial—by conventional medical practitioners, Dana says it's a central part of homeopathy because symptoms are viewed as the body's effort to restore health, not as something "wrong" with the body. "Homeopathy is entirely based on augmenting the body's own immune and defense system, and it's the only system of medicine, ultimately, that respects the wisdom of the body and then seeks to mimic that wisdom," he says.

• The Homeopathic Revolution: Why Famous People and Cultural Heroes Choose Homeopathy by Dana Ullman

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