Andres Garcia, a barrel-chested, aging Mexican soap-opera hunk, tells TV viewers nightly that it saved his life.
Botanicas, Hispanic herbal shops, can't keep it in stock.
And the demand for it has grown so much in the last year that it's replaced coca plants - the source of cocaine - as a top crop for many farmers in the highlands of Peru.
A decade ago, only naturalists, environmentalists and Indians in the Peruvian Amazon had heard of the giant, wood-like ivy known as una de gato: cat's claw. These days, after a blitz of TV infomercials and Amway-style sales rallies, una de gato is the new Laetrile for Hispanics in the United States and Latin America - promising miraculous cures for everything from cancer and the common cold to ulcers and AIDS. Millions have seen the ads on Spanish-language television and responded.
In the largely unregulated world of vitamins and herbal treatments, no one really knows if the pills, teas and powders they purchase contain una de gato. The same uncertainty is true for the health claims made by manufacturers, some of which violate Food and Drug Administration rules by stating that una de gato can cure any of a dozen ills - including rheumatism, arthritis, tumors and diabetes.
But while the plant does contain a chemical known to kill cancer cells, there are no long-term studies in humans indicating that the plant can cure any disease.
A bigger problem is that copycat versions of una de gato have
made some people sick. In September, botanists and horticulturists in South Texas warned people not to buy una de gato products made from an unrelated poisonous shrub found along the U.S.-Mexican border. The shrub, Acacia greggii, which is also called una de gato because of its claw-like thorns, contains cyanide.
Nonetheless, hype over the so-called "miracle plant" is so great that vitamin manufacturers worldwide are rushing to order huge quantities of it from Peru, where the government estimates it has become a $100 million-a-year industry.
Latin American immigrants, many of whom are distrustful of doctors and Western medicine, have responded overwhelmingly to the bombardment of Spanish-language ads for the product. In una de gato, they find hope of cures for illnesses that have no cures and confirmation of long-held beliefs in the healing powers of plants.
Concepcion Contreras, 49, a Mexican immigrant who lives in Newark, Calif., gets tears in her eyes when asked if she thinks una de gato will subdue her 14-year-old daughter's brain tumor.
"She's suffered so much"
"I pray to God that it does," she said, holding a bottle of the product in her hand. "She's suffered so much with operations and pills and medical tests that we thought we'd try something new. Until now we've never tried alternative medicines, but I've heard of so many people getting cured with this, that I thought it was worth a try."
The competition in the una de gato market is fierce. Door-to-door salesmen peddle the product in Hispanic neighborhoods nationwide. So do frequent "Call Now" ads on Spanish-language television. And herbal shops nationwide stock more than a dozen varieties of una de gato teas, pills and even chewing bark.
At Botanica De La Rosa in San Jose, Calif., una de gato products are in the store's prime display spot: next to the cash register. Owner Gilberto De La Rosa, a white-haired man with a hearty laugh, attributes the brisk sales to Garcia, the Mexican actor who claims on television commercials that una de gato cured his prostate cancer.
De la Rosa marvels at the product's amazing ability to "cure" and "purify."
"I'm using it myself," he said in Spanish.
"There's nothing wrong with me really, but it's made me feel younger, more energized," he said, flexing his arm.
No known side effects
The plant doesn't have any known side effects, even in large dosages, Cornell University plant biologist and chemist Dr. Eloy Rodriguez said, adding that he didn't think it was dangerous for people to take it.
The FDA said this week there had not been any complaints filed by people using the plant.
Nevertheless, FDA spokesman Brad Stone said it was illegal for una de gato manufacturers and retailers to make health claims on the packaging, advertising and marketing of the dietary supplement.
"People should understand when they buy these products, we cannot guarantee their safety or effectiveness," Stone said.
But health claims are common and were made during a recent visit to De La Rosa's shop. With the purchase of several bottles, the cashier included a photocopied pamphlet stating the conditions treated by una de gato. A distributor of the product - aware he was in the presence of a reporter - told the cashier it was illegal to do so and the cashier then removed the pamphlet from the bag.
Distributors go to great lengths to differentiate their brands. Sales people such as Sally Nieto of Fremont, Calif., play up concern about low-quality products. She said she could guarantee that her una de gato, bottled by vitamin-maker New Vision, contained at least 400 milligrams of the plant in each capsule. Other companies are not trustworthy, she warned.
Nieto told an audience at a recent informational meeting that the plant "cured" her breast cancer.
She and other pitchmen offered the mostly working-class Hispanic audience una de gato and seven other dietary supplements, including vitamin C and grape seed anti-oxidants - for a monthly cost of $430. When audience members complained about the price, Nieto told them they could earn their capsules for free by marketing to their friends and family.
"It's your choice," she said. "Those of us who are sick and have chosen to use these products are still here. Those who haven't, aren't around today."
But in an interview, Nieto said she didn't know if she was cancer-free or not. She said she started taking una de gato after having surgery to remove a breast tumor. She said she was taking una de gato instead of having the chemotherapy and radiation treatments her doctor advised.
"I cannot tell you how much better I feel," she said. "I am not falling over tired any more. I am also not having hot flashes from menopause. I can tell you that I would not be alive today if it wasn't for this."
Like Nieto, hundreds of believers are helping to spread the reputation of una de gato. And whether it cures them or not, their faith in the product is making some people rich.
Jorge Garcia, 55, a Peruvian immigrant from Redwood City, Calif., understands that. The kitchen worker at San Mateo County General Hospital has spent almost $2,000 to import una de gato.
Sales have been slow, but they are starting to pick up.
"My main reason for doing this is to help those who are suffering without hope," he said.
What about making a profit?
"Well, nothing wrong with that too," he said, smiling.