Caffeine’s Competitors: Coca, Khat, Ephedra, Betel, and Yohimbé
Caffeine is not the only naturally occurring stimulating alkaloid that has been consumed as a beverage, food, or masticatory. Here is a brief description of some other botanical uppers and their sources.
Coca
The coca plant (Erythroxylon coca) is a small tree or shrub with tiny white flowers native to the region of the Andes Mountains. The natural source of the drug cocaine, the leaves have been mixed with powdered lime and chewed by natives as a stimulant and panacea since ancient times.
Usually planted from seeds, the seedlings are raised in a nursery for up to ten months. Once replanted, the amount of cultivation lavished on them varies with the size and location of the plantation. When the tree is about six feet tall, pickers, in the spring and again in the fall, gather the leaves, which are then cured and dried, before being powdered for local use or sold for extraction. When supplies from South America fell short of worldwide demand, coca was cultivated in the East Indies, with the result that much of the legal international trade originates in Java.50
In the regions to which it is native, powdered coca leaves are freely available in local markets. The chewing is a general practice among Andean laborers, who claim that, as a result of their use of the leaves, they can work for days with little food or rest. Distances in the region are sometimes reckoned in cocadas, the range that can be traversed on one chew. The admixture of lime is considered indispensable to producing any effect, and lime is similarly used in commercial processing to extract the alkaloid, cocaine.
Coca leaf use creates an apparently minimal detriment to the people who chew it and the society in which they live. In striking contrast are the detrimental effects of using extracted cocaine, a practice generally associated with personal instability, drug dependence, paranoia, violence, and eventual psychosis. The reasons for these marked differences are unclear. Scientists point to the slower rate of absorption from chewing as compared with smoking or injection, to a different set of social mores, and suggest that there may be other active alkaloids in the leaf that moderate the effects of cocaine in a way that is not achieved when the extracted chemical is consumed by itself. The fact is that science today has not solved the mystery of these disparate effects, and a similar uncertainty and confusion surrounds the differences between the effects created by each of the plants listed in this section when compared with the effects of the chemical extracts of each plant’s “active principle.” We like to think that our contemporary science has all the basic answers, but insofar as understanding the way these psychoactive plants do what they do, the answers still elude us.
Khat
In 1892, when James Walsh published his book on tea, he mentioned an “Arabian tea” that he called “Cathadules,” which he said was prepared from the leaves of shrub “extensively cultivated there for that purpose, as much attention being bestowed upon it by the natives as on coffee. This preparation is sometimes also called ‘Abyssinian tea.’” He observed, “The leaves are also chewed, when green, like those of the coca in South America, being highly intoxicating, particularly in the wild state.”51
Khat (qat, kat, chat, murmungu, mirra, or miraa), or Catha edulis, is an evergreen shrubby tree whose fresh leaves and young twigs are chewed for their stimulating effect and is also the name for the popular beverage brewed from its leaves and used by millions in a wide area of East Africa and the Middle East. But it is in the Yemen, the traditional home of coffee, that khat’s use has for centuries been a pervasive social institution that colors family, work, and recreational activities and associations. Although its consumption is general in the Yemen among men, women, and children, in neighboring countries its use is more limited. For example, it is reported that truck drivers are the primary regular users of this plant in Kenya.
Ever since khat came to European attention from its widespread use in the Middle East, it has been assumed to contain the same stimulant as coffee and tea. Therefore the active ingredient was, on analogy with “caffeine,” given the name “cathine.” Today it is known that khat contains no caffeine but does contain several active chemicals, some of which are alkaloid stimulants structurally similar to amphetamines. Cathinon is thought to cause the primary stimulant qualities of khat, while cathine and norephedrene are said to contribute to its other somatic effects, such as brachiodilation, or enlargement of the passages leading to the lungs. Based on an analysis of twenty-two khat samples of diverse origins, one group of researchers determined that, in 100 grams of fresh leaves, there are 120 mg of cathine, 36 mg of cathinone, and 8 mg of norephedrine. The leaves lose their potency when they dry out, which is one reason khat use has not spread beyond the areas of its cultivation. Unlike coca leaves, the leaves of khat, which have a bitter, astringent taste, are swallowed after they are chewed.
Yemen’s extremes of altitude and variations in soil and climate make it suitable for the cultivation of a diverse variety of crops. Mediterranean fruits such as oranges and grapes are grown on the slopes, and bananas, cotton, dates, tobacco, and mangos are produced on the coastal plain. Coffee and khat are grown in the central highlands, and, together with cotton, constitute the biggest cash crops. Coffee had long been the most important export of the Yemen, famous for its superior mocha, so called because, in the sixteenth and seventeenth centuries, Mocha was its primary port of egress into the world market. Though the best Arabian coffee, among the most prized and expensive anywhere, is still grown in the Yemeni district of San’a, coffee cultivation is losing ground to the more profitable cultivation of khat, for Yemeni khat, like Yemeni coffee, is considered to be of superior quality. Strange to say, the Yemen, which all the world thinks of as the first home of fine coffee, has become intensely preoccu pied with the use of a different psychoactive stimulant plant, to the extent that coffee there, in both use and cultivation, has been relegated to a distant second.
In 1996, Hamza Hendawi, in an Associated Press article datelined San’a, Yemen, described how “from the finest private homes to the dusty streets…almost every man in Yemen chews khat.” He explains that government officials are concerned because a majority of the male population is stoned for at least part of every day. The bitter leaves are chewed slowly, forming a small ball that chewers roll around in their cheeks, as tobacco chewers do with snuff. In 2000, a bundle of six to ten branches sells for between fifty cents and fifty dollars, depending on its quality. A typical khat fix costs about three dollars, a staggering sum in a country with an average daily per capita income of about a dollar a day.
A common sight is men walking home from the market carrying bundles of khat. Khat chewing is often done at home during daily sessions that can bring together two dozen or more men from early afternoon until evening. However, taxi drivers, street vendors, and businessmen often chew it during the working day, and students chew it to keep awake at night while studying for exams. Ali Abdullah Saleh, the president of Yemen, a khat lover himself, still makes certain his troops receive their daily rations, as he did during their conflict with rebels in southern Yemen a few years ago.
In 2000, Donna Abu-nasr, in another Associated Press article datelined San’a, reports how increasing numbers of women are becoming regular khat users as well. After primping and scenting themselves for the occasion, they gather in their own version of afternoon tea, parties at which a light meal of sandwiches and desserts accompanies khat chewing and intoxication. Tea and soft drinks are frequently served to alleviate the dry mouth that is a side effect of Khat consumption.52
Khat nay-sayers include Mohammed Yehia al-Sharafi, a neuropsychiatry professor and head of Yemen’s University of Applied Sciences, who says that although small doses can reduce anxiety, regular use—and it is used with uncanny regularity —causes gastritis, inflammation of the gums, depression, poor appetite, and loss of sexual potency. Sharafi believes that most of khat’s attraction is the way it imbues its users with a sense of inspiration, a feeling of being fu
ll of important ideas that merit long, ebullient speeches. Khat’s proponents, who in addition to the president include many prominent citizens, see in the drug the encouragement of some of the same desirable social effects that coffee’s early proponents adduced. “Khat sessions remove all social divisions and bring together men from different walks of life,” comments Wad’ai, one of Yemen’s most respected judges and himself a devoted khat chewer. Besides, according to Wad’ai, “It is not addictive as people say. That is why we don’t need it when we are traveling outside Yemen.”
In a country in which khat cultivation consumes 75 percent of the irrigation water and occupies more than 80 percent of the arable land, an important goal of some factions in the government has been to decrease the production and use of khat. But an active trade has continued despite their attempts. Like the recurring efforts in many countries throughout the ages to ban caffeine-containing beverages, these measures enjoyed little success.
Ephedra
Ephedras are leafless desert bushes native to arid regions throughout the world. They are related to pine trees and bear tiny cones. Several species of genus Ephedra contain the drug ephedrine, a stimulant alkaloid that is used as a treatment for asthma. Since ancient times in China, the dry stems of Ephedra vulgaris have been boiled with water to make a pleasant-tasting, although some say bitter, stimulating tea. American ephedra, which grows throughout North America, is known as “Mormon tea,” because early Mormon settlers used it instead of caffeinated beverages, which are prohibited by their religion. Ma-huang, made from the more potent Chinese species Ephedra sinica, Ephedra equisetina, and Ephedra intermedia, has been a traditional medicine in China since well before the introduction of tea in that country. Until the development of synthetic ephedrine, the alkaloid extracted from these species was used in the West as the basis for nasal and bronchial remedies for relieving congestion and to treat low blood pressure.53 Today, extracts from these plants are common ingredients of herbal stimulants sold in health food stores. The FDA has recently warned about the dangers of the increasingly common use by the young of ephedra products as intoxicants and diet aids, especially when they are compounded with caffeine.
The plants are harvested in autumn, dried in the sun, and cut into pieces. When used as a powdered medicinal, the pieces are boiled in water, sometimes with honey, and then roasted until dry. It is still prescribed in China for typhoid, colds, coughing, and as a painkiller. Today, synthetic ephedrine and a closely related compound, pseudonorephedrine, are ingredients in dozens of prescription and over-the-counter allergy and cold medications.
Betel
“Betel” can refer to either of two unrelated plants, the areca palm, known as the “betel palm” (Areca catechu), or the betel pepper, known as the “pan plant” (Piper betle). The “betel nut,” or seed of the areca palm, is wrapped in the so-called betel leaf of the betel pepper, and the two are chewed together as a stimulant throughout southern Asia and the East Indies. Many Western readers will be surprised to learn that chewing betel is a steady habit for about 10 percent of the world’s population.54
The areca palm, first described by Theophrastus (374–287 B.C.) in about 340 B.C., is cultivated in India, Sri Lanka, Thailand, Malaysia, and the Philippines. Its unbranched trunk can reach fifiy feet but is only about one and a half feet around, with a cluster of up to a dozen palm fronds sprouting from the top. The fruit, about the size of an egg, has a tough rind that contains a hard seed, or nut. The fruit is picked in the fall, before it is fully ripe, and is husked, boiled, and finally sun-dried until it turns dark brown or black.
The stimulating ingredient in betel nuts is the alkaloid arecoline, a drug used by veterinarians as a worming agent. (This is not the same as “black catechu,” an extract for dyeing and tanning, which, confusingly enough, is taken from the wood of the areca palm.)
For more than two thousand years the natives of the regions where the “betel palm” grows have used this combination drug.55 Betel chewing was recorded in China by the fourth century, where the nut, then as now, was known under its Malay name, “pinang.” Travelers to the Far East have long noted the habit among the natives. Marco Polo in the thirteenth century and Ibn Batuta in the fourteenth century described how betel was consumed together with the areca nut and lime and noted its intoxicating effects. Polo tells us:
You should know that these people, and indeed all the peoples of India, are addicted to the habit, which affords them some satisfaction, of carrying almost continually in their mouths a certain leaf called tambur. They go about chewing this leaf and spitting out the resulting spittle. This habit prevails especially among the nobles and magnates and kings. They mix the leaves with camphor and other spices and also with lime, and go about continually chewing them. And this habit is very beneficial to their health.56
As we have seen, Bacon mentions the drug in 1627 in Sylva Sylvarum, describing how it is chewed with lime, in a list of intoxicants that includes opium, tobacco, and coffee. In the first quarter of the twentieth century, Lewin, who did extensive field research into psychoactive botanicals, observed:
The passion for the drug is common to all, both men and women, to every age and class: princes, priests, workmen, and slaves consume it. All religions participate. Christians, especially coloured missionaries, Mohammedans, Buddhists, Brahmans, Fetishists, and other sects. All races are addicted to the drug, Caucasians, Mongols, Malays, Papuans, Alfurus, etc.57
Those who enjoy betel prepare to chew the dried pieces of the nut of the areca palm by wrapping it in the fresh leaf of the betel pepper smeared with a lime paste and perhaps flavored with cloves, tamarind, or other spices. The use of the betel pepper leaf and lime increases salivation and helps to bring out the active alkaloids of the areca nut. When the betel nuts and leaves are chewed, a large amount of red saliva is pro duced, which temporarily colors the gums and lips. However, the practice does not stain the teeth black, as has sometimes been claimed, an error arising from the fact that some of the chewers deliberately stain their teeth black for cosmetic effect or have poor nutrition and dental hygiene.
Yohimbé
Yohimbé is the bark of an African tree (Corynanthe yohimbe) containing a crystalline alkaloid stimulant called “yohimbine.” The bark has an acrid, spicy flavor and has been used for centuries in central Africa as an aphrodisiac. In the United States, yohimbé bark is occasionally available at herb stores and can be brewed into an invigorating tea for use as an aphrodisiac. Some say it causes tingling feelings up and down the spine.
Some scientists say that yohimbine stimulates sexual arousal by irritating the urinary tract, as do cantharides found in powdered blister beetles (a folk medicine administered to male livestock to encourage breeding that is sometimes called “Spanish fly” when used by people).58 Others say that its aphrodisiac reputation is simply the result of the power of suggestion, because the stimulating powers of yohimbé are produced only when it is consumed in toxic doses. Still a third faction suggests that there must be other, unknown active constituents in yohimbé bark, because yohimbine alone does not seem to produce the same effects as the bark extract.
Yohimbine, perhaps the main active constituent in yohimbé bark, is an alpha-2 adrenergic antagonist. Alpha-2 autoreceptors act as a kind of thermostat to regulate adrenergic activity. Some of the noradrenaline released by a neuron returns to its alpha-2 autoreceptor, which then reduces the amount of noradrenaline it secretes. This cybernetic control mechanism is similar to a thermostat, which registers the temperature and reduces the amount of heat produced when the air warms up. Unlike simple agonists, which universally activate receptors, yohimbine, by blocking the alpha-2 autoreceptors, actually induces an amplification of noradrenergic activity.
Yohimbine is an ingredient in some folk medicines sold around the world to treat impotence, as increased adrenergic activity seems to help stimulate sexual function. Yohimbine is contraindicated in people with high blood pressure, heart problems, or problems with anxiety
, all of which can be exacerbated by increased adrenergic activity. It should never be combined with any other stimulant or any monoamine oxidase (MAO) inhibitor.
PART 5
caffeine and health
15
caffeine and the body
Health Effects, Reproductive Issues, and Fitness
What is it in man’s devious make-up that makes him round on the seemingly more wholesome and pleasurable aspects of his environment and suspect them of being causes of his misfortunes? Whatever it is, stimulants of all kinds (and especially coffee and caffeine) maintain a position high on the list of suspicion, despite a continuing lack of real evidence of any hazard to health.
—Editorial, British Medical Journal, 1976, I:1031
Coffee and caffeine have long been suspected of causing illnesses ranging from myocardial infarction, arrhythmias, hypertension, hyperlipidemia, gout, and anxiety, to fibrocystic breast disease, various cancers and birth defects, and osteoporosis. No other agent in the human environment has been as frequently associated with such a variety of chronic-degenerative, even malignant diseases.
—Siegfried Heyden, “Coffee and Cardiovascular Disease,” 1993
Caffeine and, before caffeine was identified, coffee, tea, and chocolate, have been said to cause, exacerbate, palliate, or cure an enormous variety of diseases and have also been said to confer marvelous benefits, including increases in both intellectual and physical capacities. If, like the great majority of people in the world, you use caffeine regularly, you are faced with a complex, confusing, and often apparently contradictory cacophony of traditional and contemporary claims about its effects on human health. In former centuries, caffeine lovers had no guidance but the often fanciful discourses of the medical men of their time. We are fortunate that, in the last half of the twentieth century, a explosion of general medical knowledge and a large number of controlled experiments have shed scientific light on many of caffeine’s effects. It has been often and truly said that caffeine is the most studied drug in history. Yet, because of its nearly universal use, the variety of its modes of consumption, its presence in and effects on nearly all bodily systems, and its occurrence in chemically complex foods and beverages, together with the complexity of the social and psychological factors that shape its use, caffeine may also be one of the least adequately understood. Despite tremendous scientific scrutiny, many central health questions about caffeine remain unanswered or even unaddressed.
The World of Caffeine Page 39
