Medicinal Plants: An Introduction

Imagine, for a moment, that you are a Cherokee hunter living on the wide open plains of the American west.  You and your brothers have embarked on a long hunting trek in search of big game.   You must move efficiently, and light, and you must subsist on the land along the way, carrying as few provisions as possible.

You arrive at a river, and collect an assortment of edible plant parts for food: cattails, wild berries, dandelion roots and leaves, wild seeds.  This, plus your satchel filled with pecans, sunflower seeds, and dried corn flour, will provide a nutritious and energy-packed meal throughout the day.  You then pick up your track, and continue the hunt, equipped to restore to the body the energy you are expending on your trek.  However, your trek continues long into the night, and the herd is moving faster than you expected.  Time and distance are beginning to work against you, and you are starting to feel exhausted.

A brother finds a stand of Yaupon Hollies among a cluster of oak trees near a small creek.  He breaks off several stems while you quickly prepare a small fire.  Another brother prepares a ceramic bowl with water and places it over the fire with rocks.  You roast the Yaupon leaves over the fire, and add the leaves to the steaming water.   When this roasted-yaupon leaf tea is finished, and cooled, your brothers drink this tea, extinguish the fire, and move on into the night.  And you did this because you knew that yaupon leaves contain a special kind of “energy.”

This “energy” is know to modern science as caffeine.  So, in effect, this “hunter’s tea time” is kinda like the equivalent  of a stop at Starbucks on the way to work.  The Yaupon tea doesn’t really provide any nutritional energy.  The leaves contain a secondary metabolite that is a chemical analog of a special kind of neurotransmitter in the human nervous system.   Modern science has defined this secondary metabolite as “caffeine”, and of course we know of many other plants that produce caffeine.  In Asia, the Camellia genus of plants is known to produce caffeine, among other beneficially healthful chemicals.   Green Tea, and Camellia-based teas are known and consumed the world over.  In a similar vein, the plant Theobroma cacao native to the Central American tropics, contains caffeine, among over 60 other secondary metabolites.  The seeds of this plant were fundamental to Mayan mathematic and economic systems.  The fresh seeds were added to chilies and a host of other aromatic spices to produce a frothy beverage that was consumed by the greatest Mesoamerican kings of Pre-Columbian history.   Today, we call this chocolate.

And of course, no mention of caffeine would be complete without a quick nod to that morning cup o’ joe.  The seeds of the plant, Coffea arabica, are roasted, ground, and pressed into a rich, watery “tea”, and consumed the world over by people needing a stimulating neurological boost before work.

Thus, it is clear how the secondary metabolites of plants can be used to enhance the function of individuals within culture and improve the survivability of both.  This is not just an occasional trend; this is a trend that has occurred throughout our existence on this planet.   Plants are not just integral to our dietary subsistence needs, but to the cultural/medical/spiritual needs of our mind and body as well.  Chocolate was, in a way, a “divine” substance to the Maya and Aztec people.  Erythroxylum coca was likewise a divine leaf to the Andean and Incan people of north western South America where it provided a pharmaceutical adaptation to life in high-altitude environments.  Archaeologists have found Ephedra and Hemp seed residues in ancient burial sites across Asia and western Europe.   Opium was a major commodity traded along the Silk Road.  These are all plants that do not in all cases provide dietary subsistence resources, but perhaps something even more valuable than that, the resources of a spiritual/ medical/ economic nature that effectively enhances social organization.

In the early twentieth century, scientists began studying opiate drugs to determine more precisely how the drugs acted in the central nervous system.  This research led to the discovery of internally-produced (“endogenous”) opiates that scientists named “endorphins”, a shortened form of “endogenous morphine”.   Scientists were able to isolate the specific chemical molecules that acted on targeted neuro-receptor sites, and thus, drugs like morphine were developed that enhanced the survivability of patients and war-time soldiers alike.  Likewise, scientists isolated the specific chemical compound in Coca leaves, and developed amphetamines and analgesics used both in surgery and to keep war-time aircraft pilots alert during combat.

Aspirin was originally discovered in Willow trees (Salix genus).   The chemo-therapy drugs vinblastine and vinchristine were discovered in the plant Catharanthus roseus.  Anti nausea and anaesthetic drugs were originally discovered in a range of plants in the Nightshade family, include Belladonna and Brugmansia.   Today, scientists are developing drug compounds to treat pain and muscle spasms targeting endogenous CB1 and CB2 cannabinoid receptors,  this discovery spurred by the investigation of the active chemical components of “marijuana” flowers.

Plants have been used by humans throughout history for diverse applications of medical treatment.  Yarrow was applied to battlefield wounds in the Roman era.  Dianthus was used in Europe as a blood thinner.  Wormwood was used in Europe, Asia, and Africa to expel intestinal parasites.  The addition of Turmeric in Asian-Indian food preparation is associated with lower incidents of heart disease and strengthened immune systems.   These plant compounds are effective because of the unique chemistry each contains, a chemistry that humans have learned to use beneficially over time.  This is as true today as it was 10,000 years ago.

All plants produce secondary metabolites to some degree, although the chemistry varies from species to species.  The diversity inherent to “medical botany” is often cause for immense confusion and skepticism.  To compound the matters, the chemistry of each plant changes over the course of the plant’s life cycle.  Plant chemistry can vary according to seasonal changes, lunar cycles,  day length cycles, and even during the course of a single day.  After a compound is harvested, the potency of a chemical might degrade quickly over time.  There are numerous obstacles like these that keep science from fully embracing botanical pharmacology.  The perceived natural “randomness” of botanical medicine is difficult for the objective lens of science to measure.  Thus, we in the modern world tend to be skeptical of plant medicines, a skepticism deeply rooted in our ignorance.   But, this skepticism is without warrant.  On the contrary, it is holding modern medicine back.

It use to be that embedded within a cultural population were specialists whose central role was to study and understand botanical chemistry and pharmachology.  The specialists relied on knowledge passed down through the generations, this representing  a database of knowledge encompassing a deep span of time.  Every region had its own native plant population, and each plant had its own special chemistry.  Indigenous specialists understood the chemistry inherent to these plants, and often (but not always) shared this knowledge and material in trade with other cultural bodies.  By enhancing group cohesion and survivability, this helped reinforce spiritual/ religious and economic systems that provided the foundation for the agricultural revolution and the rapid expansion of human civilization.

Today, we live at the growing pinnacle of this social/ botanical co-evolution.  We are just as dependent on plants for food and medicine as we were thousands of years ago.  The difference, however, is in the quality, distribution, and reduced diversity of material that we use.  We no longer recognize a professional class of people that specialize in botanical pharmacology.   These have been replaced by modern doctors that might not know anything about raw botanical medicines, how they can be used, or possible negative drug interactions with contemporary pharmaceuticals.

When it comes to plant medicines, we have lost or forgotten much of what humanity once knew about them.  Retrieving this data will truly be a monumental effort.  It will take hard work and dedication; this will not be an easy task.  It is, however, a task worth doing, and I might argue, a task essential for the future of humanity on Earth.  I do believe that the solution to our modern health care problems will take the form of a hybrid system that utilizes natural medicines and contemporary pharmaceutical knowledge.    But, this system has to be built from the ground up.  And really, this system begins and ends with personal responsibility.


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