Echinacea, St. John's wort, valerian-these exotic dietary supplements are becoming household names in a society eager to maintain its youthful vigor. Seniors, too, are increasingly turning to supplements as a way to stave off deadly diseases, such as Alzheimer's Disease and fight prostate cancer. But before you rush out to buy these modern marvels, consider their downside.

"Just because it's labeled as a dietary supplement and a 'natural' product doesn't mean it's safe," says Dr. Jeffrey Blumberg, professor of nutrition at Tufts University. According to Dr. Blumberg, dietary supplements fall into two distinct categories.

The first category is what he terms "nutritional supplements," representing the traditional vitamins, minerals, proteins and fiber found in the major food groups. By definition, supplements are meant to do just that-they supplement the substances normally found in foods.

The second category, botanicals or herbal products, are also considered "dietary supplements," but they are more problematic. Although named "dietary" supplements, they are not normally found as a natural part of our diets.

"We never eat Echinacea or St John's wort or saw palmetto oil," Blumberg says. In fact, Blumberg prefers to call these supplements "phyto-medicines."

That's not to say these botanical medicines don't work. On the contrary, the traditional medical community is finding many of these phyto-medicines have considerable healing powers. For example, clinical studies have shown that St. John's wort is helpful in treating cases of mild depression. Ginkgo appears to slow the progression of Alzheimer's in patients with the disease.

According to Blumberg, the problem arises when individuals attempt to diagnose these conditions themselves. Seniors with a number of ailments may be especially vulnerable to inflated claims of a product's miraculous healing powers, and may take it upon themselves to try one of these phyto-medicines. After all, it couldn't hurt, right? Wrong.

In fact, older Americans may be especially susceptible to the chemicals in these products. As with other medicines, seniors may suffer toxic effects of substances at lower levels than for younger adults. Moreover, seniors typically take a variety of other prescription medications, which makes them prime candidates for harmful drug-herbal interactions.

"A perfectly safe botanical is not safe for folks taking other medications," warns Blumberg. "Potential side effects can range from allergic reactions to kidney failure, seizures, and even death."

Also, unlike most vitamins and minerals, phyto-medicines have few recognized standards of purity and uniformity. The product label is not always a reliable indication of what's in the bottle. If possible, stick with recognized name brands, which are more apt to provide uniform doses of the supplements' active ingredients.

Most importantly, consult with a physician, nurse or pharmacist about your medical condition. Express your interest in treating it with dietary supplements. While some physicians may be skeptical of supplements, others are more accepting of their use by patients. This dialogue is especially critical if surgery becomes necessary.

"If you're about to undergo surgery, you really have to tell your doctor about everything you take, including dietary supplements," Blumberg says.

In many cases, patients are reluctant to tell their doctors about the herbal remedies they use, perhaps embarrassed or afraid of the doctor's reaction. Or perhaps they simply don't consider it important enough to mention.

Taking dietary supplements is often viewed as a way of empowering seniors to take control of their own health. However, consumers should do some research before impulsively purchasing a particular supplement by reading as much as possible about the supplement in magazines, newsletters, or reliable websites.

In short, the term "natural" does not mean "harmless." These supplements can have a positive impact on your health, provided you handle them with care.

He Knows His Stuff!

Jeffrey Blumberg, Ph.D, is an antioxidant expert and serves as associate director at Tufts University's Human Nutrition Research Center. He also serves as an advisor to the Tufts Health and Nutrition Newsletter. Dr. Blumberg's research has appeared in many leading journals.