(FORTUNE Magazine) – An informed consumer is the best customer, but have you tried navigating your way through the maze of health information in the news these days?

How's this for a headline: RADISHES MAY PREVENT CANCER. The headline, which goes with a hypothetical study I just made up, is guaranteed to attract more attention than EXTRACT P38 DECREASES DNA MUTATIONS IN VITRO, but it's a little over the top. In most cases the media are not blatantly reporting inaccuracies, but sometimes you have to wonder.

In this particular case, everyone runs out to buy radishes until the next study comes along. People tend to believe the most recent finding, particularly if it involves doing something easy like popping a pill. But what about context and perspective--how do radishes fit into the bigger picture?

While it sometimes seems that medicine changes in large leaps, it's actually more of a slow evolution; single studies are rarely revolutionary. I would interpret the "radish study" in the context of the American Cancer Society's dietary guidelines, which begin by recommending that we eat more plant products. My hypothetical study is consistent with this and supports what people should be doing already. But many other vegetables may offer protection against cancer; there's probably little that's unique about radishes.

The quality and types of information are important. A study that was done in a test tube or on animals is not the same as a randomized, controlled trial in humans. While hundreds of compounds act like antioxidants in a test tube, not all provide clinical benefits to humans. Example: vitamin E. While basic lab, animal, and epidemiologic (population) studies have generally supported a role for vitamin E in decreasing the risk of heart disease, thorough clinical trials have not shown that it produces much benefit.

When you hear some new or unusual health information, check out the source, its credibility, and its potential biases. Companies that market vitamin E will emphasize studies that report potential benefits and ignore better-done clinical trials that may not be as positive. Other sources with a vested interest, financial or otherwise, can be suspect.

Anecdotal findings are also suspect, particularly when they're about patients who dramatically recover from a disease after an unorthodox treatment. I love the one about the 80-year-old who has smoked his whole life; what's missing is the fact that 20 of his smoking buddies died. In general, we shouldn't let anecdotes guide our beliefs or clinical practice. We need documented evidence from well-done studies.

Ultimately, staying healthy usually means getting back to the basics. Thousands of studies support eating well, exercising, and not smoking--and are unlikely to be changed by the next sensational study that comes along promising the fountain of youth.

For more information on this topic: Go to mayoclinic.com. Mayo Clinic offers Executive Health programs at Mayo Clinics in Jacksonville, Fla.; Rochester, Minn.; and Scottsdale, Ariz.