Monday, June 22, 2009

Herbal Medicine: Herbal Tradition (Part II)

"Virtually all of the new plants and drugs that excited the medical world of the sixteenth and seventeenth centuries were exotics," Barbara Griggs writes in her history of plant medicine, Green Pharmacy. "From 1602 when England at last signed a peace treaty with Spain, imports of the plants from the Spanish colonies had increased by leaps and bounds."

According to Griggs, about 70 percent of the plant stocks of the European apothecaries were imported from either the Far East or the Americas, including medicinals such as sarsaparilla, balsam of Tolu, balsam of Peru, and sassafras. Writing and compiling material in the sixteenth century, the Spanish prelate Sahagun also reported about a variety of purges, diuretics, febrifuges, and sedatives the Aztecs used, including balsam of Tolu, sarsaparilla, and valerian.

One of the biggest botanical discoveries during the post-Conquest period in the New World was the bark of the cinchona tree, which had for years been used by the Indians of Peru and Ecuador to treat malaria, a disease that had ravaged parts of the Mediterranean. The legend sometimes repeated in historical accounts is that a Spanish soldier sick with malaria drank from a pool of water into which a cinchona tree had fallen. Chemicals of the tree bark had seeped into the water, which revived the ailing soldier. There are other legends about the discovery of the restorative powers of this special rain forest tree. But historians generally agree that it was a European missionary who in 1663 first reported the indigenous use of cinchona bark, telling his order about a tree growing in Peru "which they call the Fever tree in the country of Loxa, whose bark is the colour of cinnamon ... it has produced miraculous cures in Lima." Eventually Jesuits shipped the bark back to Rome, where one cardinal, after being cured by the substance, ordered that every sample of the bark have a little leaflet with instructions on how to mix it in a glass of white wine in order to cure a fever, according to Griggs's historical account of that period. There was business intrigue over cinchona, too. One British apothecary, James Talbot, set himself up as a fever specialist who promoted his own cure over the use of cinchona. He gained wide renown and warned customers against using cinchona. But according to Griggs, after Talbot's death, in 1682, Louis XIV of France revealed that Talbot had in fact been using a mixture of rose leaves, lemon juice, wine, and an infusion of cinchona.

The flow of medicinal plants was not only from the New World to the Old. During the colonial period, a great many plants from Europe and the Middle East found their way to the Americas, where they were able to thrive in the hospitable climate and become a part of the local folk medicine practices. Chamomile, rue, and rosemary all became firmly planted in the herbal apothecaries of Latin America—as any visitor today to the herbal stalls in San Jose's Mercado Central can plainly see.

The herb stalls in San Jose, piled high with medicinal plants, have the appearance of a cornucopia. The tramos cater to a market that very much believes in the efficacy of the folk remedies. But it is also a belief, it seems, that comes without a reliance on the spiritual and magical elements more prevalent farther north, in Mexico and the Caribbean. The herbs are used, Costa Ricans say, because people believe they work, not because of magic.

The lack of reliance on the spiritual elements in Costa Rica is illustrated by the way the herb merchants sell their wares. No religious symbols are evident, no towering figures of saints or deities. Instead, hand-printed on white sheets of paper with black and red ink are the names in Spanish or English of various maladies or organs the plants are believed to be useful for: prostata (prostate), asma (asthma), impotencia (impotence), leche materna (mother's milk), nervios insomnio (insomnia), and so on. Under each ailment are listed the names of effective medicinal plants and how they are to be used.

Botanists have noticed some interesting differences between the indigenous medicinal plants and Western-style drugs, something that is evident from a perusal of the market signs in the San Jos6 herbal stands. Balick and his colleague Paul Alan Cox have noted that indigenous plants are more often used for "gastrointestinal (GI) complaints, inflammation, skin ailments, and ob-gyn disorders, whereas Western drugs are most often used to treat disorders of the cardiovascular and nervous systems, neoplasms [i.e., cancer], and microbial ailments."

Why is there such a difference? The reasons are found within the lifestyles of the cultures. Cardiovascular illness, cancers, microbial infections, and nervous system problems are bigger killers in Western cultures, compared with the lifestyles of indigenous peoples, who tend not to live as long and see diarrhea, maternity problems, and inflammations as more serious, wrote Balick and Cox. In fact, other researchers have noted that it has not been unheard of for infant mortality in some Amazon tribes to reach an astonishing 30 percent, with more than half of the deaths among children under one year old attributed to diarrhea, dysentery, or respiratory infections. Balick and Cox have also noted that traditional cultures are likely to avoid plants containing toxic substances that, while perhaps useful against cancer and cardiovascular problems, have a narrow dosage window that requires sophistication in the way they are used.

This is illustrated as well by the shortlist of medicinal plants that, under Costa Rican law, can be sold for remedial purposes. Under the Costa Rican practice, the market tramos can sell the medicinal plants as vegetables in their natural state. But once they are sold in stores as extracts, powders, soaps, or pills, the harvesting and processing of the plants are supposed to be more tightly controlled. At least in theory, the plants have to be properly identified, their chemical components must be assayed, and their purity acceptable. In-practice, however, Costa Ricans say it is difficult to ensure that all of the medicinal plants harvested meet the expectations.

It turns out that while Costa Ricans traditionally rely on scores of medicinal plants, only a handful are officially recognized as safe for documented health-related uses. The shortlist includes chamomile, thyme, sarsaparilla, and mint verbena. Even though such plants have numerous traditional medicinal uses, under the Costa Rican regulatory scheme they are recognized for use either as an intestinal antispasmodic or to help urination, the kinds of physical problems that Balick and Cox note are most often treated with plants by indigenous peoples.

This modest listing of documented plants in Costa Rica, despite a vast cultural experience in Central America with plant medicine, is typical of what has gone on elsewhere. Very often governments, world organizations, and regulators have moved more cautiously, though at different paces depending upon location, in recognizing plants for use as folk medicine.

Standing by any of the herbal stalls in the San Jose market provides a visitor with a view of some of the most widely used medicinal plants in Hispanic cultures, from the southwestern United States and Mexico to South America. In fact, the most commonly used plants among Mexicans and Costa Ricans are similar. Asked which remedies they use most often, Mexicans on both sides of the Rio Grande in cities in Texas and Mexico listed chamomile, aloe vera, rue, anise, mint, wormwood, orange tree leaves, sweet basil, oregano, garlic, and rosemary. All but orange tree leaves are available in the Costa Rican market. Some two thousand miles south, in a women's health clinic in Chile, chamomile, oregano, rue, and rosemary are the key ingredients of a number of remedies listed in a recipe book. Clearly, while there are regional variations, there exists a basic core knowledge of herbal medicines among the many Latin cultures that stems from both the ancient Indian and the European peoples.

A sense of how deeply entrenched the use of medicinal plants is within the cultures of Latin America can be determined from a number of recent studies, some ongoing. There are so many plant species in Latin America that it has been impossible so far for any one group of researchers to determine all of the medicinal plants available. But one study in particular, focusing on the Caribbean basin and Central America, had by 1999 identified and studied 109 plants used in traditional healing practices. The review, done by the organization Traditional Medicine in the Island (TRAMIL), surveyed rural populations to find out which plants were commonly used to treat illnesses (serious conditions such as cancer and AIDS were excluded). Next they reviewed the chemical composition of the individual species, identified potential dangers, and made recommendations on their use. The results are published in a Caribbean pharmacopoeia and are part of an overall strategy by TRAMIL to spread valuable knowledge about safe medicinal plants and encourage their cultivation in order to provide Central Americans and Caribbean islanders with an affordable alternative to Western-style drugs.

About'one-tenth of the plants surveyed by TRAMIL are considered toxic and their usage is discouraged. But a majority of the plants are either still under investigation or are considered to be safe. Among the latter are a number of medicinal plants familiar to the Hispanic cultures and sold by the hierbas vendors throughout the region: chamomile, peppermint, eucalyptus, ginger, papaya, annatto, and others. It is the same core group of medicinal plant products found continually throughout the Latino world.

Were they to work at herbal stands outside of Costa Rica, merchants such as Alfredo and the Asturias family would undoubtedly feel comfortable knowing that their products would be in demand among the local populace. Still, the herb vendors of San Jose have been facing uncertainty about where they might be conducting business in the years to come. Rumors keep circulating in the Mercado Central that some developers are interested in razing the hundred-year-old structure and building a modern complex. Some of the merchants simply do not know what the rebuilding plan would mean for them or if they would be able to stay. But if the herb traders did move, the customers would undoubtedly seek them out.

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