Remedy Research: Some Hints, Few Answers
By NANCY BETH JACKSON
Published: January 26, 1999
Eager to relieve the agonizing symptoms of winter viruses, sufferers are widening the search for remedies well beyond the conventional treatments. But even as Americans gobble $12 million worth of vitamins, herbs and supplements annually, scientists and others say there is not enough solid research to evaluate their effectiveness.
That, however, is beginning to change.
Last fall, alternative medicine drew attention when The Journal of the American Medical Association published its first issue devoted to herbal medicine. Other journals are also reporting on such therapies.
Here are some of the findings about the effectiveness of several popular alternative treatments.
ECHINACEA Called the most popular herb in the United States, echinacea is generating more than $300 million in sales annually. Although a 1992 study of the use of echinacea demonstrated a significant decrease in symptoms and duration of flulike illness, a review of 12 commonly used medicinal herbs published in the Archives of Family Medicine in November noted that of 26 published controlled trials evaluating the plant, none were conclusive.
The review, with lead authors from the University of Washington, concluded: ''Available evidence on echinacea's therapeutic potential is incomplete, but does suggest a possible supportive role in treating infections and wounds. However, well-designed clinical trials are needed to substantiate echinacea's efficacy, clarify appropriate dosages and confirm safety.'' For boosting immune systems, dosages have not been standardized, but the 1992 study suggested a link between benefits and dosage.
In the same issue, Dr. Dieter Melchart of the Center for Complementary Medicine Research in Munich, Germany, reported the results of a clinical trial in which 302 volunteers received either one or two echinacea extracts or a placebo. The 12-week study found echinacea no more effective than a placebo in preventing colds.
GARLIC With a long history in the kitchen and in warding off colds and vampires, garlic is one of the most extensively studied medicinal herbs. Louis Pasteur identified its antiseptic properties in 1858.
Results from recent clinical trials attempting to confirm other uses have been mixed, according to the Archives of Family Medicine herbal review. In late 1997, Antimicrobial Agents and Chemotherapy, the journal of the American Society for Microbiology, reported the discovery of a molecular mechanism that might explain some of garlic's medicinal uses. Scientists at the Weizmann Institute in Israel contend that allicin, the main biologically active component of garlic, blocks certain enzymes associated with bacterial, fungal and viral infections.
VITAMIN C Linus Pauling, who won the Nobel Peace Prize and the Nobel Prize in Chemistry, launched a controversy still being played out in laboratories around the world when he published a book, ''Vitamin C and the Common Cold,'' in 1970, asserting that vitamin C could prevent colds. He later expanded his theories to include flu and cancer. He advocated taking at least 1,000 milligrams of vitamin C daily and took 18,000 milligrams a day himself, although the recommended daily allowance is 60.
No conclusive data have shown that such large doses significantly protect against the common cold, but many people remain convinced. The recommended daily allowance is under scrutiny, with the National Institutes of Health recommending an increase to 200 milligrams.
Meanwhile, vitamin C turns up in various over-the-counter remedies and foods, and the Japanese have even added it to cola.
ZINC LOZENGES Zinc lozenges as a cold remedy surfaced with George Eby, a Texas math major who became a city planner then fell into biomedical research in 1979 when his young daughter, suffering from leukemia, had a severe cold. The cold appeared cured after a crushed zinc gluconate tablet dissolved in her mouth. By 1984, Mr. Eby was reporting tests in which the lozenges significantly reduced how long cold symptoms lasted. In 1996 a Cleveland Clinic study found that sucking on zinc gluconate lozenges reduced the duration of cold symptoms although the lozenges tasted bad and 20 percent of the people who took them reported nausea. Later trials have been less conclusive. Mayo Clinic specialists suggest caution for children, pregnant women and people with chronic kidney or liver disease.
Photo: Folk wisdom extols garlic, but studies haven't yet proved that it actually wards off illnesses.