Jul. 03, 2012

Excerpt from "Out of Nature": The Role of Plants in Medicine

by Kara Rogers

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The following is an excerpt from chapter 6 of my book Out of Nature: Why Drugs From Plants Matter to the Future of Humanity (University of Arizona Press, 2012). Nearly half of the world's 300,000 known species of plants currently are under threat of extinction -- a symptom of the widening disconnect between humans and nature. Out of Nature discusses this disconnect in the context of plants and medicine, with special emphasis on biodiversity conservation. -- Kara Rogers
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As more has become known about plants, it has become clear that they are not only extraordinarily important to modern medicine, but against the backdrop of increasing knowledge of the world’s climate and environment, many species are extremely fragile. The rarity of many medicinal species in the wild and the inability of rare species to survive under cultivation have defied the will and the strength of humans. Still, we find ourselves drawn to them, fascinated by them. In attempting to understand these species, the realization of their significance to modern science, to human survival, and to Earth’s biodiversity has brought new meaning to medicine and conservation.
The majority of remedies used in systems of medicine that have been practiced since ancient times are plant based. Most of the people who rely on these medicines live in countries in Asia and Africa, where traditional medicine is practiced exclusively by about four-fifths of the population. Such remedies, however, are relevant not only in societies where the presence of conventional medicine is lacking. Between 70 and 80 percent of people in developed countries have used some type of complementary or alternative treatment. (Complementary medicine is used alongside conventional medicine, whereas alternative medicine is used in its place.) These forms of treatment include the use of over-the-counter products containing plant materials, as well as reliance on therapies such as massage and acupuncture. In conventional medicine, about one-quarter of prescription drugs contain bioactive chemicals derived from plants, and close to two-thirds of anticancer drugs are based on chemicals extracted from natural sources. There also are numerous drugs derived from compounds found in bacteria, molds, and other organisms.
The global value of plant-based medicines is most readily apparent in revenue generated from sales of over-the-counter herbal preparations. In 2005 more than $14 billion (USD) was spent on such remedies in China alone. In 2007 US citizens spent even more -- nearly $15 billion -- on over-the-counter natural products. Ginseng, ginkgo, echinacea, garlic, feverfew, saw palmetto, and kava kava ranked among the most frequently used herbal remedies. The amount of money spent on these products accounted for nearly 44 percent of all out-of-pocket expenses on complementary or alternative medicine in the United States in 2007. The surprising element of this is that the safety or efficacy of most nonprescription natural products is unproven. A small quantity, just micrograms, of a substance may be enough to exact a cure, but the average person buying an over-the-counter “natural” herbal remedy is often buying an extract that is too concentrated or that may not even be natural at all. Unapproved drugs facilitate self-medication, a dangerous and risky approach to healing for people unfamiliar with the physiological effects of the substances they use. Yet, when faced with the hurdles of privatized health care and the often exorbitant costs of conventional medicine, people would rather take matters into their own hands.
The decision to use traditional, complementary, or alternative treatments entails much more than dollars and cents. There is a greater, holistic sense of healing associated with these approaches, perhaps because they articulate the organic side of medicine. In the case of traditional practices, lifetimes of knowledge lie behind the art of mending human ailments. This does not mean, however, that we should consider every treatment applied in traditional systems of medicine to be all-healing. Some are not physiologically beneficial at all and benefits attributed to others may actually be the result of an associated placebo effect. Other concoctions may even harm the body. But within the extensive corpus of traditional knowledge there exists a wealth of plant remedies that scientists can turn to for investigation. Perhaps more importantly, there also endures a connection to the natural world, an aspect that is wanting in conventional medicine and many modern societies in general.
But conventional medicine produces proven, tested medicines, and it has saved more lives already than any other form of medicine in history. Much of its success has stemmed from the discovery of life-saving drugs, and in order for this to continue, in order for drugs new to medicine to emerge in the coming years, nature must become a part of modern discovery, with its role alongside synthetic discovery reestablished. In recent years, realizing that many species of plants may yet be discovered, scientists have found renewed hope for medicine and the healing of human disease. In the process, they have thrown into startling relief the need to protect the world’s plants.
From Out of Nature: Why Drugs from Plants Matter to the Future of Humanity by Kara Rogers © 2012 The Arizona Board of Regents. Reprinted by permission of the University of Arizona Press.
Learn more about Out of Nature at the book's Web site. Read a review here (pdf).
About Kara Rogers

Kara is a freelance science writer and senior editor of biomedical sciences at Encyclopaedia Britannica, Inc. She is the author of Out of Nature: Why Drugs From Plants Matter to the Future of Humanity (University of Arizona Press, 2012).

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