Herbal remedies

There's no magic

March 27 1997

Name an ailment. Any ailment. Somewhere in the world there's an herbal remedy suggested for it. For many conditions there are dozens of purported herbal remedies, and some herbs are touted to cure almost everything.

Popular interest is skyrocketing in products from plants believed to have medicinal value. But do herbs actually work? Are they safe?

Dr. Donald D. Hensrud is a Mayo Clinic preventive medicine and nutrition specialist who examines vitamin and herbal supplements. He says questions of safety and effectiveness must be answered herb by herb — using the best available scientific data.

Unfortunately, in most cases such data are insufficient. "Many believe herbs are a panacea. Others believe they have no value," Dr. Hensrud says. "As is often the case, the truth probably lies somewhere in between, although proven value is lacking for most herbal products."

If your neighbor says an herbal product worked for him, that does not constitute proof of benefit. The "placebo effect" may be at work. Conversely, lack of proof does not mean there is no benefit. "It may be that the appropriate studies have not been performed," Dr. Hensrud says. "However, each herbal product should be judged on the data available and the quality of that data. For most herbs, there are few good controlled studies." Disillusionment with conventional medicine partly explains the growing interest in herbal products. For many, sipping a "natural" tea is more appealing than popping a synthetic pill. However, if you are interested in herbal treatments, Dr. Hensrud offers the following points of perspective:

  • Not magic: "There is nothing magic about herbs," he says. "Whatever health effects they possess is due to the pharmacologic properties of their active ingredients. Herbs may contain many different ingredients and it may be difficult to determine the exact composition and also which ingredients are responsible for any observed effects."

  • Some good, others toxic: It's safe to conclude that some herbs are potentially beneficial and others are toxic. However, "for most herbs current data does not support much benefit or toxicity," Dr. Hensrud says. "For herbs with potential benefit, the degree of benefit, if present, is mild in most cases."

  • Dosage: The amount and type of ingredients in herbal products can vary with differences in soil, growing and harvesting conditions. This often makes it difficult to get a consistent dose. Consuming wild herbs is dangerous unless you know exactly what you are ingesting.

  • Lack of standards: There is an overall lack of quality controls for herbal products and dietary supplements. An act of Congress in 1994 reduced the U.S. Food and Drug Administration's regulatory control of dietary supplements and herbal products. As a result, such products can be marketed without proof of either effectiveness or safety. In addition, health-food stores and web sites can make health claims about unproven products as long as they avoid assertions that these products cure or prevent specific diseases. It's common to see such statements as "improves the immune system" or "slows the aging process" on the labels of products even though there is no research on humans to support these assertions.

  • Whole foods: For people seeking to promote wellness and prevent disease, Dr. Hensrud suggests a proven path — a healthful diet emphasizing a wide variety of unprocessed and low-fat whole foods. "Virtually the entire population could improve their nutrient intake through healthier dietary changes," he says. "For example, fruits and vegetables are excellent sources of many nutrients and at least five servings daily are recommended. Yet fewer than one person in three consumes this amount."

Get the facts

Reliable information is the best remedy for unrealistic claims offered for any medicinal product. "Every herb is different from every other herb," Varro E. Tyler, Ph.D., a professor of pharmacognosy (the study of natural drugs) at Purdue University, writes in the preface to his book, The Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies, which examines the properties of more than 100 popular herbs. "Some are safe and effective. Some are neither. As is the case with other drugs, the administration of herbs may produce undesirable side effects."

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