Step right up, folks!

FORGET penicillin. The Revigator was the real medical breakthrough of the 20th century. It cured diabetes, high blood pressure, arthritis, “inflammation of the uterus” and many other maladies. Or so the ads claimed.

The Revigator, a water jug lined with radium, is no longer available in stores. Somewhere around 1930, the general public lost interest in a product that made their lemonade and coffee dangerously radioactive.

These days, few people -- we hope! -- would be gullible enough to believe that radioactive water could cure all of their ills. But many of us are happy enough to believe in the healing powers of magnetic bracelets or infrared lamps. And just a couple of years ago, people flocked to buy Seasilver, a big-selling blend of seaweed, aloe vera and other herbal ingredients that was purported to cause permanent weight loss while curing AIDS, cancer, anthrax and nearly 650 other diseases -- enough to make the Revigator look like a sugar-pill dispenser.

Health products have changed over the decades, as have many of the buzz words they use to lure customers: Today’s products are more likely to “harmonize” and “optimize” than to “revigorate” or “revitalize.” They’ve also updated their sciency-sounding claims.

An electric belt sold in the 1900s exploited the “principle of the voltaic pile” to restore a patient’s “vital or nerve force.” At the time, electricity seemed new and magical.

Today, a bottle of Colloidal DNA Boost gives consumers a chance to enjoy the “bioenergetic repatterning signal of healthy DNA,” a claim that clearly plays on the public’s fascination with genes and genetic engineering.

And yet many things have stayed the same since the days of the Revigator -- or, for that matter, the days of horse-drawn carts filled with snake oil. Marketers still tout miracle devices, magic pills and instant health, promises that continue to sell no matter how often they’re repeated and recycled. Hucksters also continue to profit on hopes, faith and desperation, natural resources that will never run out.

By law, ads and labeling for over-the-counter health products can’t be false or misleading. But enforcement is so light and sporadic that the law is barely noticeable on the airwaves, the Internet or drugstore shelves. In fact, says Matthew Daynard, a senior attorney in the Federal Trade Commission’s advertising practices division, ads and product packages are minefields of deception, misdirection and outright fraud. Some products, he says, live up to their billing and deliver on their claims, but many other promises go unfulfilled.

“Consumers should be highly skeptical of claims made for any pill, patch, cream or device,” Daynard says.

Since the FTC and the Food and Drug Administration don’t have enough resources to go after every product sold under false pretenses, Daynard says, it’s largely up to consumers to protect themselves and put deceptive marketers out of business. “We like to think of consumers as our agents in the field,” he says.

Nobody can possibly keep track of all the latest medical advances or health products, but consumers can learn to spot the tell-tale signs of bogus remedies and false promises, says Dr. Brent Bauer, director of the Complementary and Integrative Medicine Program at the Mayo Clinic in Rochester, Minn. “People have to do their own homework.”

Staying vigilant is hard work because it goes against our basic human instincts, says Joe Nickell, a senior research fellow with the Committee for Skeptical Inquiry who has investigated bogus Mexican cancer clinics and other forms of quackery. The deep desire to feel better can easily push aside questions and doubts, he says. “Quack treatments appeal to emotions. People stop thinking with the organ above their neck. They think with their heart or their gut.”

We may know more about health and medicine than previous generations, but all of that progress hasn’t dampened our wishful thinking, especially in the face of illness, Nickell adds. “A little voice may tell you that it’s a long shot, but you put that voice aside,” he says.

The fickle nature of health makes it easier for people to believe in worthless products, Nickell says. Symptoms naturally fade in and out. By chance, some people are bound to feel better after trying the latest pill or elixir. And thus, another believer is born.

Before you stake your health or your money on this or that product, the first thing you can do is some online sleuthing. Check to see if a device has really won FDA approval by visiting the “devices@FDA” link. (It’s at www.accessdata.fda.gov/scripts/cdrh/devicesatfda.) Likewise, www.ftc.gov lists companies that have been targeted by the FDA or FTC for unfair or illegal marketing practices. Experts also recommend Consumer Reports on Health (www.consumerreports.org/main/crh/home.jsp) as a reliable, unbiased source of information on dietary supplements.

That’s a good start. But you should also watch for these calling cards of quackery.

* Scientific smoke and mirrors. In the modern marketplace, even reassuring phrases such as “scientifically tested” and “546% more effective” can be red flags, Daynard says.

Unless consumers can verify the studies with a reputable source -- perhaps a medical journal or a website of a major health organization -- they can’t be sure the study ever existed or that the results are meaningful or relevant.

Marketers treasure vague, pseudoscientific words that sound good but mean little, Bauer says. For example, many pills, patches and devices promise to “detoxify” the body but never say which toxins will be removed. Even fewer provide a plausible explanation for how the alleged toxins leave the body.

For creative use of scientific-sounding lingo, it’s hard to top an Internet ad for Colloidal DNA Boost, a product that is “formulated to produce a specific harmonic frequency that optimizes DNA function and may retard degenerative states such as cancer, arthritis, and other autoimmune types of imbalance.” Bauer says it’s safe to put this product in the “fishy column.” The only way to improve DNA, he notes, is to change the code, a process also known as “mutation.” He doubts that any type of “harmonic frequency” could shuffle DNA. People who truly want mutations in a bottle will have to look elsewhere.

Many ads use scientific studies to win customers -- even when science isn’t really on their side. For example, one website selling magnetic bracelets, necklaces and anklets describes a small Scandinavian study showing that incontinent women had fewer leaks after sitting in a magnetic chair for 20 minutes twice a week for eight weeks. But the site doesn’t describe how women could get the same benefits from a bracelet or necklace. It also doesn’t mention follow-up studies that found no link between magnetic fields and incontinence.

* The list of potential uses is longer than the list of ingredients. “Anytime a product claims to cure a thousand different things, I don’t believe it,” Bauer says. And examples of cure-alls abound. An Internet ad for the Healing Lamp claims that infrared rays can successfully treat at least 75 conditions, including heel spurs, angina and Crohn’s disease -- ailments that have practically nothing in common beyond their supposed willingness to fade under a warm light.

And then there’s Seasilver, the now-notorious supplement marketed by Seasilver USA and Americaloe. Ads for Seasilver went beyond a mere laundry list of uses. As recently as 2003, marketers claimed that the supplements could take the place of actual, potentially life-saving medications. The most egregious (and potentially deadly) claim: 9 out of 10 diabetes patients who used the product could supposedly stop taking their insulin.

In 2004, the FTC filed suit to force the marketers to refund $3 million to customers and stop making false claims. The defendants dawdled on payments and in July, the FTC slapped marketers with a fine of nearly $120 million. A check of the Seasilver website shows that the claims have softened considerably. The product that once “cured” 650 diseases is now simply touted as “what nature intended.”

* Treatment claims. The shelves of health food stores are loaded with relatively unambitious products that claim to treat just one disease at a time. But even these modest claims are dubious as well as illegal, Daynard says. By law, marketers aren’t allowed to claim that herbs and dietary supplements can cure or treat any specific condition.

Some marketers, it appears, take this law about as seriously as pedestrians regard jaywalking ordinances. Researchers from Harvard Medical School surveyed 338 websites selling herbal products. As they reported in 2003, more than half of the sites illegally claimed to cure, treat, prevent or diagnose particular diseases.

Bauer encourages his patients to stay away from any products that make such promises. Any company that flagrantly breaks the law shouldn’t be trusted, he says.

The FDA does allow specific health claims for a select few vitamins and minerals with proven benefits. For example, calcium tablets could claim to “reduce the risk” of osteoporosis, and folic acid can legitimately be said to reduce the risk of certain birth defects. But even these nutrients have to stop short of calling themselves “cures.”

A cautionary note: Consumers who want to try a dietary supplement or herbal product should talk to their doctor first, Bauer says. Doctors can recommend particular products and warn about any known side effects or conflicts with other medications.

* A promise to “promote.” Supplements can legally claim to “promote” the health of specific body parts as long as they don’t mention a particular illness. Countless products offer variations on the theme. Some say they promote prostate health while others claim to promote health of breasts or bladders or brains. Such phrases can’t be trusted, says Dr. Stephen Barrett, vice president of the National Council Against Health Fraud and longtime crusader against medical quackery.

“The word ‘promote’ is a weasel word,” he says. “It means nothing.” The FDA doesn’t test such claims, leaving marketers free to decide which body parts they want to promote.

The FTC could theoretically go after a company that falsely claimed to promote health, but it would be difficult to challenge such a vague term in court, Daynard says.

* Weight-loss miracles. Until the general public embraces the only proven methods for long-term weight loss -- eating less and exercising more -- unscrupulous marketers will prey on their hopes for a quick fix. The weight-loss industry is “ripe for abuse, exaggeration and fraud,” Daynard says. “People are still looking for a magic pill.”

The FTC has been urging newspapers, radio stations and other media outlets to stop carrying misleading ads for weight-loss products. Some of the offending ads have disappeared -- including television commercials for Fat Seltzer, a supplement that claimed to cause permanent and substantial fat loss without dieting -- but consumers can’t let down their guard, Daynard says.

Consumers should be on the alert for several well-worn claims favored by weight-loss profiteers, according to the FTC. Over-the-counter products are probably too good to be true if they promise to block absorption of fat or if they claim to cause weight loss no matter how much a person eats or exercises, the agency says. And any product that promises weight loss of more than 3 pounds a week is bound to fall short.

* All-natural ingredients. Lead, arsenic and rattlesnake venom are all-natural products, but you wouldn’t want them in your multivitamin. Not all herbs are safe, either. In 2004, the FDA banned the sale of supplements containing ephedra, a natural stimulant that raised the risk of heart attack or stroke.

* Echinacea or lawn clippings? Because the FDA doesn’t routinely monitor the contents of supplements, Bauer urges his own patients to choose only products that have been certified by the USP (U.S. Pharmacopeia) or NSF International. These organizations, upon the request of manufacturers, will verify the contents (but not the effectiveness) of supplements in independent laboratories. Without such reassurances, consumers can’t trust that the product even contains the promised active ingredient. A 1995 Consumer Reports survey of 10 ginseng products found that some were 10 to 20 times more potent than others, differences that weren’t reflected in labels. The testing also weeds out products loaded with impurities -- among them, pesticides and rat hairs, Bauer says.

Another option is to look for products manufactured by large pharmaceutical companies such as Bayer, which have entered the alternative market. “A $100-billion company isn’t likely to risk its reputation by bottling grass clippings and calling it echinacea,” Bauer says.

* Testimonials and money-back guarantees. Marketers often try to deflect doubts by using these confidence boosters. But such tactics should make customers feel less secure in their purchases, not more. According to a recent report from the FDA and FTC, testimonials and money-back guarantees are often red flags for bogus products.

Testimonials are often either completely fictitious or bought and paid for. Reputable companies use other methods to sell their products.

As for risk-free trials or money-back guarantees, companies often fold up shop before they have to issue refunds, a strategy that’s especially easy in this age of Internet marketing. In other cases, companies simply decide to do other things with the money. For example, in November, an Iowa court ordered Vision Improvement Technologies to stop selling its See-Clearly Method -- a kit of charts, videotapes and audiotapes that supposedly improved vision -- and refund $200,000 to customers. According to the court judgment, unsatisfied customers were unable to get refunds despite a promise of a 30-day risk-free trial.

As the See-Clearly episode shows, supplement makers certainly haven’t cornered the market on outlandish advertising and misleading practices. Health devices from magnets to passive exercise machines are often promoted with claims that would embarrass the most jaded supplement salesman.

* FDA-approved? Marketers of devices often try to win confidence by saying that their products are FDA-approved.

The alleged stamp of approval shows up on Internet ads for the Chi Machine, for example, a therapeutic massager that supposedly eases pain and improves circulation by jiggling the legs back and forth. One site claims that the machine is an “FDA Approved Class 1 medical device.”

But in this case and many others, the words “FDA-approved” don’t promise anything. In response to our inquiry, the FDA’s Center for Devices and Radiological Health, or CDRH, says that claims for the Chi Machine are “false” and “highly misleading.”

The FDA does classify the Chi Machine as a Class 1 medical device, -- but all that means is it is considered harmless. The agency never tested the product’s effectiveness or approved it for anything.

A website for the Kinohimitsu Health Pad -- a product that allegedly removes toxins through the skin -- takes the tactic a step further. Users who click on the words “FDA Approved” are directed to a website featuring two official-looking certificates, one of which prominently features the words “FDA Certified.” The certificates, however, “don’t mean anything,” according to the CDRH. “They were issued by a private laboratory and do not mean that the product complies with FDA regulations.”

Arizona Unipole Magnetics, a company selling magnetic mattress pads and other magnetic products over the Internet, claims that the healing powers of their products have been confirmed in “FDA-qualified” studies conducted by Dr. William Philpott.

The CDRH says it has no knowledge of Philpott’s studies and can’t vouch for his mattress pads, one of which sells for nearly $3,000.

In a telephone conversation, Philpott, 87, of Choctaw, Okla., says he has been studying magnets for nearly 20 years with “beautiful results” and has written a book on the subject but has not submitted any data to the FDA or published a peer-reviewed scientific study on magnets or any other topic.

Before spending $3,000 on a magnetic mattress pad or any other pricey product with purported health benefits, consumers should ask hard questions of themselves. The pad may or may not help, but it will, indisputably, cost $3,000.

“A person who has $3,000 to spend on his health might consider joining a gym or buying a lot of healthy food instead,” Bauer says.

There are a few tried-and-true ways to improve health, among them those old classics: Eat right, exercise, don’t smoke, get plenty of sleep. But until proven otherwise, every quick fix is probably just another incarnation of the Revigator -- minus, one hopes, the radioactivity.