The fast-growing elderly population, especially those in chronic pain, are prime targets for quacks.

"Profit and deceit," says Dr. Victor Herbert, chief of the hematology and nutrition laboratory at the Bronx Veterans Administration Medical Center, and author of several books on health fraud. "That's exactly what quackery is."

After a two-year investigation, a subcommittee of the House Select Committee on Aging last year concluded that health fraud steals $10 billion a year from Americans 65 and older.

"People are most susceptible to quackery when they feel helpless, when they feel hopeless and when they feel not in control of their own fate," says Herbert. "And when people are suffering from chronic pain, they feel most helpless and hopeless and not in control of their fate."

Herbert spoke last week at a conference on chronic pain, sponsored by the National Council on the Aging and the National Chronic Pain Outreach Association.

Separating fact from fiction in health claims can be difficult, Herbert warns. True cause-and-effect is often indistinguishable from mere coincidence, suggestibility or the natural history of the illness.

For example, in a study of soldiers treated for battlefield injuries during World War II and the Korean War, a doctor secretly substituted saline (salt) solution for morphine in the injections for some troops, all of whom thought they were getting morphine.

Surprisingly, two thirds of the soldiers injected with saline said they got just as much pain relief as those who received morphine, and only 10 percent complained of getting no pain relief from it.

"Suggestion is a very potent force," Herbert says. "It can reduce or eliminate real pain."

What is wrong, then, with a drug or product that works only by power of suggestion, also known as the placebo effect?

Nothing, says Herbert, as long as the product is not harmful. But if, like many drugs and treatments, it is potentially dangerous, "there's a lot wrong with it."

He cites three products that are often touted as painkillers even though they are unproven -- and potentially toxic:

*DMSO, or dimethyl sulfoxide, is often promoted for relief of arthritis and cancer pain, even though that claim has never been proved by scientific studies, Herbert says. And the Arthritis Foundation last year issued an alert that DMSO, taken together with Clinoril, an anti-inflammatory drug, can produce severe, permanent nerve damage.

*Vitamin B6 is often promoted as a cure and preventive for the painful symptoms of premenstrual syndrome. Scientific studies show that it's no better than a placebo. But does that mean it's harmless? Not necessarily, says Herbert. The vitamin -- a vital nutrient present in fish, poultry, meat, cereals and green leafy vegetables -- can cause nerve damage when it is consumed in large supplemental doses of more than 200 milligrams a day.

"There's a common misconception that anything that is natural is safe," Herbert says, "and if some is good, more is better. That's not true."

*Laetrile, an extract of apricot pits, was widely touted as a cancer treatment in the 1970s and still rings up $1 billion a year in legal and illegal sales. Repeated scientific studies have found it worthless as a cancer treatment. Since laetrile is 6 percent cyanide, it's also potentially toxic.

Herbert cautions consumers to ask two basic questions about any purported painkiller: Does it work, and is it safe?

To answer those, he says, one must ask whether the treatment has been shown objectively to be more effective than doing nothing, and at least as safe as doing nothing. And if it's not as safe as doing nothing, then it should be used only if the potential benefit outweighs the potential harm.