Q: I’m interested in using herbal supplements. What do I need to know?
Answer from Kimra Hawk, R.D., L.D., Outpatient Dietitian, and Terese Scollard, R.D., L.D., M.B.A., Regional Clinical Nutrition Manager: First, discuss with your physician the herbs you are planning to take. As more and more Americans turn to herbal remedies, it’s become clear that "natural" substances, including herbs, can have harmful side effects, just as medications can. For example, kava – a popular herb for reducing anxiety – has been taken off the markets in several countries because so many of its users developed liver damage.
Think of herbs as medication and always get advice from a qualified health professional about how to take them safely. If you diagnose and treat yourself, the herbs you choose could interact with other vitamin supplements or medicines and cause health problems. For example, St. John’s Wort, an herbal remedy for mild depression, appears to weaken the effect of certain cancer drugs used in chemotherapy.
It can be particularly risky to have surgery while taking certain herbs. Garlic, ginkgo and ginseng can increase the risk of bleeding during or after surgery, and valerian can increase the sedative effects of the anesthesia. The American Society of Anesthesiologists recommends that you stop taking these herbs, as well as many others, at least two weeks before surgery.
To choose the best brand of herbs, look for herbal extracts that are standardized and made by companies that follow good manufacturing practices. These brands will carry the United States Pharmacopoeia (USP) or National Formulary (NF) mark on the package or label. The USP or NF seal does not mean, however, that the herbal product is safe, nor does it prove that it has any health benefits.
To reduce the chance of side effects, stick with single-herb products that clearly show how much you get in each dose. Also, be sure you are buying the specific part of the plant (for example, the root, leaf, stem or flower) that research studies have found to be effective.
Lastly, the Food and Drug Administration cautions that five herbs are particularly dangerous and should be avoided: belladonna, comfrey, broom, lobelia and pennyroyal.
Pregnant and breast-feeding women need to take special caution in checking first with their health care provider. Ditto for children – even before giving an herbal drink or tea. The Federal Trade Commission is placing a special focus on deceptive marketing of supplements for children. In June 2004, a congressional committee heard testimony about a wide range of unproven supplements aimed at children. The products promised to prevent colds, treat attention deficit/hyperactivity disorder (ADHD) or help children lose weight, safely and naturally; but some of the products contained unsafe stimulants, hormones or herbs.
The bottom line when it comes to using herbals: Do your homework. Below are some reputable sites for the latest information on herbal products.
The National Center for Complementary and Alternative Medicine supports rigorous research on complementary and alternative medicine (CAM), trains researchers in CAM, and distributes information to the public and professionals on which CAM practices work, which do not, and why.
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