April, 2000: China
Ephreda is both the common name and the Latin genus name for a plant that has been used medicinally for 5,000 years in China, where it is known as "ma huang." Today it is in widespread use as a treatment for asthma, emphysema, sinusitis, bronchitis, whooping cough, low blood pressure, and circulatory insufficiencies. Most recently, however, a derivative of Ephedra has gained popularity in the battle of the bulge.
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Joint fir, Ephedra, part of a single plant. (From Stern, Introductory Plant Biology, 8th edition, © 2000 McGraw-Hill Companies, Inc.)
Ephedra, the only genus in the family Ephedraceae, is a shrublike gymnosperm. Its aerial stems are generally collected before the first frost in autumn when the alkaloid content is highest. The active component isolated from Ephedra is an alkaloid known as ephedrine, C10H15NO. Alkaloids are a major class of natural products that have a physiological effect in other organisms. They characteristically contain carbon, hydrogen, nitrogen, and in many cases, oxygen. Because of their potent pharmacological effects, alkaloids are the basis for many pharmaceuticals, both prescription and nonprescription. Ephedrine is categorized as a sympathomimetic agent, one that targets the sympathetic nervous system, the division of the autonomic nervous system that stimulates such physiological processes as heartbeat and respiration. Ephedrine can be obtained synthetically or extracted from one of two main species of Ephedra, either E. equisetina or E. sinica. As a bronchodilator used in asthma and related disorders, ephedrine relaxes the smooth muscle of the small bronchial tubes in the lungs, increasing their diameter.
As a diet aid, advocates of Ephedra-based supplements claim it decreases appetite, raises metabolism, burns fat, and improves concentration. The effect on appetite has been documented, and there is also support for the claims of improved concentration and increased metbolism and their subsequent invigorating effects because Ephedra is a vasodilator and circulatory stimulant. Also, although there is no scientific evidence that Ephedra-based products directly burn fat, they do increase blood flow and energy levels, thereby potentially making exercise more productive. Because of this, athletes and other fitness advocates strongly support Ephedra-based products as a natural complement to their workouts. Overall, these supplements and diet aids are literally flying off the shelves. For example, sales of Metabolife, an Ephedra-based diet supplement, were expected to reach $900 million in 1999.
It is a common misconception that anything derived from nature is good and harmless, while in reality plants make some of the most toxic chemicals known to science. Also, phytochemicals (plant chemicals) can have widely varied reactions in different people. The Ephedra-based products carry warning labels specifying that they should not be combined with other medications and should be avoided by persons with such ailments as heart disease, high blood pressure, and diabetes. In addition, dosage guidelines of no more than 25 mg at a time, not to exceed 100 mg a day, have been put forth by the American Herbal Products Association, an organization that sets standards and guidelines for the diet supplement industry. Nevertheless, problems have arisen, and to date several deaths have been associated with ephedrine-containing products. The specifics surrounding these cases are a source of contention; however, taking the product in excess amounts or failing to heed warning labels may be implicated in some. One individual reportedly took eight ephedrine-based tablets at once (more than four to six times the recommended dose), and another abused ephedrine-caffeine combinations.
Although over-the-counter (OTC) drugs are subject to approval for safety and effectiveness by the Food and Drug Administration (FDA), herbal dietary supplements such as Ephedra-based products are considered food items and are therefore not subject to premarket screening. However, in 1983, reports of harmful effects gave the FDA leverage to begin attempting to ban ephedrine-containing diet products. One ephedrine-caffeine combination sold as an OTC drug was successfully banned from the market.
Meanwhile, the Dietary Supplement Health and Education Act (DSHEA) of 1994 acknowledges that dietary supplements can be beneficial and urges consumers to freely choose these products based on the scientific studies and educational materials at their disposal. Also, supporters of Ephedra-based products argue that "ma huang" has been cultivated and collected for medicinal purposes for 5,000 years in China, where it has often been taken in dosages much higher than those recommended today.
References, Websites, and Further Reading
Duffy, Mary. "Side Effects Raise Flag on Dangers of Ephedra," The New York Times, Health and Fitness, Science Times, Tuesday, October 12, 1999.
Elvin-Lewis, M., and W.H. Lewis. 1977. Medical botany: Plants affecting man's health. New York: John Wiley & Sons.
Hoffmann, David. 1997. The new holistic herbal. Rockport (MA): Element.
Wright, Jim. 1999. Ephedrine is here to stay. Flex Magazine, December, pp. 222—31.
Information on gymnosperm database links.
Information on the central nervous system.
Stern, Introductory Plant Biology, 8th edition
Chapter 2: The Nature of Life
Chemical and physical bases of life, pp. 15—18
Lipids, pp. 23—24
Chapter 22: Introduction to Seed Plants
Gymnosperms, pp. 397—415
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