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Star Bulletin Alan Titchenal & Joannie Dobbs Health Options
Alan Titchenal
 & Joannie Dobbs
                  Wednesday, February 17, 1999

 

Little known about herbal supplements

In an effort to cope with today's fast-paced, information overloaded lives, many people are turning to herbal supplements. More than one third of Americans use herbal products for health purposes, yet patients (and physicians) often lack accurate information about the safety and efficacy of herbs.

People who self-medicate with herbs often assume these products are safe because they are “natural.” However, some products can cause adverse effects or have the potential to interact adversely with prescription medications or other drugs.

Traditionally, the area of herbal supplements has been outside the expertise of medicine, pharmacology, or nutrition. Pharmacognacy is the discipline related to the pharmacology of herbs. However, herbs have now entered the food arena. They are being added to many beverages including teas and cold drinks, and are showing up in snack food like crackers and chips.

Two common herbal supplements are St. John's wort and ginkgo biloba. In the United States , they are not regulated like drugs. They are classified as dietary supplements. In countries like Germany , many herbal prod­ucts must be prescribed by a physician and herbal products sold over-the-counter must meet rigid specifications establishing potency, safety, and reasonable certainty of efficacy. Here, however, standardization of potency and quality of herb extracts is not regulated. Consequently, products can be extremely variable even from batch to batch within the same brand.

St. John's Wort (Hypericum perforatum) has been used medicinally for thousands of years and recently has been identified as an effective treatment for mild to moderate depression. In 25 controlled clinical trials where the Hypericum extract was compared with a placebo, St. John's wort was established as an antidepressant in 61 to 75 percent of patients. Side effects were mild and occurred at lower frequency than with other antidepressants. St. John's Wort also has been shown to benefit the depression related to seasonal changes.

The active chemicals in St. John's wort are thought to be similar to the antidepressant Prozac. Consequently, those using St. John's wort should take the same precautions as those taking Prozac. But this has not been studied for the St. John's wort.

Ginkgo/ginkgo biloba, another herb, has gained considerable popularity with Americans trying to enhance their memories. Ginkgo extract has been shown to increase blood flow both to the brain and peripheral tissues. The benefits from ginkgo are not well documented in America ; however, in Germany , health authorities approved a standardized extract of ginkgo (SeGb) for the treatment of some types of dementia. Before rushing out to purchase this herb or products made from this herb or products made from this herb, note reports of cerebral hemorrhaging are showing up in medicinal journals.

Herbs can offer many benefits to our long term health but only if they are taken properly.

Here are safety tips for using herbal products.

1) Rule out disease or illness prior to using herbs for a medicinal condition. Like drugs, herbs can mask symptoms and delay diagnosis of a serious illness while it progresses beyond repair.

2) Consult reputable sources about herbal preparations. Start with a book like “Herbs of Choice” by Varro Tyler. Then talk to your pharmacist about potential precautions. If your pharmacist doesn't know, he or she will know where to refer you.

3) Always tell your doctor about dietary supplements you may be taking to prevent negative interactions with other medications.


Alan Titchenal, Ph.D., C.N.S. and Joannie Dobbs, Ph.D., C.N.S.
are nutritionists in the Department of Human Nutrition, Food and Animal Sciences,
College of Tropical Agriculture and Human Resources, UH-Manoa.
Dr. Dobbs also works with the University Health Service

© 1999 Honolulu Star-Bulletin -- http://starbulletin.com
http://www.nutritionatc.hawaii.edu/HO/1998/42.htm

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