Medicinal Herbs—Some Work, Some Don't

• Anecdotal evidence has long suggested that garlic combats diarrhea caused by parasites, and international travelers are often advised to eat fresh garlic while on the road. Now, Israeli researchers have proved this claim. They found that garlic deactivates key enzymes needed by parasites to invade cells and digest food particles. Amoebas exposed to an active ingredient in garlic were killed within minutes.
• To avoid the side-effects associated with hormone replacement therapy, such as an increased risk of breast cancer, many women turn to herbal remedies to treat their menopause symptoms. Dong quai, an herb used in Chinese medicine, is commonly used for this purpose.

Despite its popularity, a new study has found that dong quai is no more effective than a placebo in treating postmenopausal symptoms such as night sweats or hot flashes. Researchers were quick to point out, however, that their study does not prove that Chinese herbs do not work for menopause symptoms. Traditional Chinese practitioners always prescribe dong quai along with other herbs, and the combined action of all ingredients may be necessary. Herbal menopause remedies sold in the U.S. typically contain dong quai alone.

• Two recent studies indicate that a boxwood tree extract may bolster the failing immune systems of people with AIDS. In a controlled study, HIV-infected patients receiving a boxwood extract progressed to AIDS significantly more slowly than those in the placebo group. Everyone who took the extract also experienced a decrease in viral load.

Based on information in: Science, 10-24-97; The New York Times, 1-13-98; The Herb Quarterly, Winter 1996