Herbalism | Wikipedia audio article

Herbalism | Wikipedia audio article


Herbal medicine (also herbalism) is the study
of the botany and use of medicinal plants. Plants have been the basis for medical treatments
through much of human history, and such traditional medicine is still widely practiced today. Modern medicine makes use of many plant-derived
compounds as the basis for evidence-based pharmaceutical drugs. Although herbalism may apply modern standards
of effectiveness testing to herbs and medicines derived from natural sources, few high-quality
clinical trials and standards for purity or dosage exist. The scope of herbal medicine is sometimes
extended to include fungal and bee products, as well as minerals, shells and certain animal
parts. Herbal medicine is also called phytomedicine
or phytotherapy. Paraherbalism describes alternative and pseudoscientific
practices of using unrefined plant or animal extracts as unproven medicines or health-promoting
agents. Paraherbalism differs from plant-derived medicines
in standard pharmacology because it does not isolate or standardize biologically active
compounds, but rather relies on the belief that preserving various substances from a
given source with less processing is safer or more effective – for which there is no
evidence. Herbal dietary supplements most often fall
under the phytotherapy category.==History==Archaeological evidence indicates that the
use of medicinal plants dates back to the Paleolithic age, approximately 60,000 years
ago. Written evidence of herbal remedies dates
back over 5,000 years to the Sumerians, who compiled lists of plants. Some ancient cultures wrote about plants and
their medical uses in books called herbals. In ancient Egypt, herbs are mentioned in Egyptian
medical papyri, depicted in tomb illustrations, or on rare occasions found in medical jars
containing trace amounts of herbs. Among the oldest, lengthiest, and most important
medical papyri of ancient Egypt, the Ebers Papyrus dates from about 1550 BC, and covers
more than 700 compounds, mainly of plant origin. The earliest known Greek herbals came from
Theophrastus of Eresos who, in the 4th century BC, wrote in Greek Historia Plantarum, from
Diocles of Carystus who wrote during the 3rd century BC, and from Krateuas who wrote in
the 1st century BC. Only a few fragments of these works have survived
intact, but from what remains, scholars noted overlap with the Egyptian herbals. Seeds likely used for herbalism were found
in archaeological sites of Bronze Age China dating from the Shang Dynasty (c. 1600–1046
BC). Over a hundred of the 224 compounds mentioned
in the Huangdi Neijing, an early Chinese medical text, are herbs. Herbs also commonly featured in the traditional
medicine of ancient India, where the principal treatment for diseases was diet. De Materia Medica, originally written in Greek
by Pedanius Dioscorides (c. 40–90 AD) of Anazarbus, Cilicia, a Greek physician, pharmacologist
and botanist, is one example of herbal writing which was used for 1500 years until the 1600s.==Modern herbal medicine==
The World Health Organization (WHO) estimates that 80 percent of the population of some
Asian and African countries presently use herbal medicine for some aspect of primary
health care. Pharmaceuticals are prohibitively expensive
for most of the world’s population, half of whom lived on less than $2 U.S. per day in
2002. In comparison, herbal medicines can be grown
from seed or gathered from nature for little or no cost. Many of the pharmaceuticals currently available
to physicians have a long history of use as herbal remedies, including artemisinin, opium,
aspirin, digitalis, and quinine. According to the World Health Organization,
approximately 25% of modern drugs used in the United States have been derived from plants. At least 7,000 medical compounds in the modern
pharmacopoeia are derived from plants. Among the 120 active compounds currently isolated
from the higher plants and widely used in modern medicine today, 80% show a positive
correlation between their modern therapeutic use and the traditional use of the plants
from which they are derived.===Clinical tests===
In a 2010 global survey of the most common 1000 plant-derived compounds, 156 had clinical
trials published. Preclinical studies (cell culture and animal
studies) were reported for about one-half of the plant products, while 120 (12%) of
the plants evaluated – although available in the Western market – had no rigorous
studies of their properties, and five were toxic or allergenic, a finding that led the
authors to conclude “their use ought to be discouraged or forbidden.” Nine plants evaluated in human clinical research
included Althaea officinalis (marshmallow), Calendula officinalis (marigold), Centella
asiatica (centella), Echinacea purpurea (echinacea), Passiflora incarnata (passionflower), Punica
granatum (pomegranate), Vaccinium macrocarpon (cranberry), Vaccinium myrtillus (bilberry),
and Valeriana officinalis (valerian), although generally there were inconsistent, often negative
results, and the studies were of low quality.In 2015, the Australian Government’s Department
of Health published the results of a review of alternative therapies that sought to determine
if any were suitable for being covered by health insurance; Herbalism was one of 17
topics evaluated for which no clear evidence of effectiveness was found. Establishing guidelines to assess safety and
efficacy of herbal products, the European Medicines Agency provides criteria for evaluating
and grading the quality of clinical research in preparing monographs about herbal products. In the United States, the National Center
for Complementary and Integrative Health of the National Institutes of Health funds clinical
trials on herbal compounds, provides fact sheets evaluating the safety, potential effectiveness
and side effects of many plant sources, and maintains a registry of clinical research
conducted on herbal products.According to Cancer Research UK as of 2015, “there is currently
no strong evidence from studies in people that herbal remedies can treat, prevent or
cure cancer”.===Prevalence of use===
The use of herbal remedies is more prevalent in patients with chronic diseases such as
cancer, diabetes, asthma and end-stage kidney disease. Multiple factors such as gender, age, ethnicity,
education and social class are also shown to have association with prevalence of herbal
remedies use.A survey released in May 2004 by the National Center for Complementary and
Integrative Health focused on who used complementary and alternative medicines (CAM), what was
used, and why it was used. The survey was limited to adults, aged 18
years and over during 2002, living in the United States. According to this survey, herbal therapy,
or use of natural products other than vitamins and minerals, was the most commonly used CAM
therapy (18.9%) when all use of prayer was excluded.Herbal remedies are very common in
Europe. In Germany, herbal medications are dispensed
by apothecaries (e.g., Apotheke). Prescription drugs are sold alongside essential
oils, herbal extracts, or herbal teas. Herbal remedies are seen by some as a treatment
to be preferred to pure medical compounds that have been industrially produced.In India
the herbal remedy is so popular that the government of India has created a separate department—AYUSH—under
the Ministry of Health & Family Welfare. The National Medicinal Plants Board was also
established in 2000 by the Indian government in order to deal with the herbal medical system.===Herbal preparations===
There are many forms in which herbs can be administered, the most common of which is
in the form of a liquid that is drunk by the patient—either an herbal tea or a (possibly
diluted) plant extract.Several methods of standardization may be determining the amount
of herbs used. One is the ratio of raw materials to solvent. However different specimens of even the same
plant species may vary in chemical content. For this reason, thin layer chromatography
is sometimes used by growers to assess the content of their products before use. Another method is standardization on a signal
chemical. Herbal teas, or tisanes, are the resultant
liquid of extracting herbs into water, though they are made in a few different ways. Infusions are hot water extracts of herbs,
such as chamomile or mint, through steeping. Decoctions are the long-term boiled extracts,
usually of harder substances like roots or bark. Maceration is the cold infusion of plants
with high mucilage-content, such as sage or thyme. To make macerates, plants are chopped and
added to cold water. They are then left to stand for 7 to 12 hours
(depending on herb used). For most macerates, 10 hours is used.Tinctures
are alcoholic extracts of herbs, which are generally stronger than herbal teas. Tinctures are usually obtained by combining
100% pure ethanol (or a mixture of 100% ethanol with water) with the herb. A completed tincture has an ethanol percentage
of at least 25% (sometimes up to 90%). Herbal wine and elixirs are alcoholic extract
of herbs, usually with an ethanol percentage of 12–38%. Extracts include liquid extracts, dry extracts,
and nebulisates. Liquid extracts are liquids with a lower ethanol
percentage than tinctures. They are usually made by vacuum distilling
tinctures. Dry extracts are extracts of plant material
that are evaporated into a dry mass. They can then be further refined to a capsule
or tablet.The exact composition of an herbal product is influenced by the method of extraction. A tea will be rich in polar components because
water is a polar solvent. Oil on the other hand is a non-polar solvent
and it will absorb non-polar compounds. Alcohol lies somewhere in between. Many herbs are applied topically to the skin
in a variety of forms. Essential oil extracts can be applied to the
skin, usually diluted in a carrier oil. Many essential oils can burn the skin or are
simply too high dose used straight; diluting them in olive oil or another food grade oil
such as almond oil can allow these to be used safely as a topical. Salves, oils, balms, creams and lotions are
other forms of topical delivery mechanisms. Most topical applications are oil extractions
of herbs. Taking a food grade oil and soaking herbs
in it for anywhere from weeks to months allows certain phytochemicals to be extracted into
the oil. This oil can then be made into salves, creams,
lotions, or simply used as an oil for topical application. Many massage oils, antibacterial salves, and
wound healing compounds are made this way.Inhalation, as in aromatherapy, can be used as a treatment.===Safety===A number of herbs are thought to be likely
to cause adverse effects. Furthermore, “adulteration, inappropriate
formulation, or lack of understanding of plant and drug interactions have led to adverse
reactions that are sometimes life threatening or lethal.” Proper double-blind clinical trials are needed
to determine the safety and efficacy of each plant before they can be recommended for medical
use. Although many consumers believe that herbal
medicines are safe because they are “natural”, herbal medicines and synthetic drugs may interact,
causing toxicity to the patient. Herbal remedies can also be dangerously contaminated,
and herbal medicines without established efficacy, may unknowingly be used to replace medicines
that do have corroborated efficacy.Standardization of purity and dosage is not mandated in the
United States, but even products made to the same specification may differ as a result
of biochemical variations within a species of plant. Plants have chemical defense mechanisms against
predators that can have adverse or lethal effects on humans. Examples of highly toxic herbs include poison
hemlock and nightshade. They are not marketed to the public as herbs,
because the risks are well known, partly due to a long and colorful history in Europe,
associated with “sorcery”, “magic” and intrigue. Although not frequent, adverse reactions have
been reported for herbs in widespread use. On occasion serious untoward outcomes have
been linked to herb consumption. A case of major potassium depletion has been
attributed to chronic licorice ingestion., and consequently professional herbalists avoid
the use of licorice where they recognize that this may be a risk. Black cohosh has been implicated in a case
of liver failure. Few studies are available on the safety of
herbs for pregnant women, and one study found that use of complementary and alternative
medicines are associated with a 30% lower ongoing pregnancy and live birth rate during
fertility treatment. Examples of herbal treatments with likely
cause-effect relationships with adverse events include aconite, which is often a legally
restricted herb, ayurvedic remedies, broom, chaparral, Chinese herb mixtures, comfrey,
herbs containing certain flavonoids, germander, guar gum, liquorice root, and pennyroyal. Examples of herbs where a high degree of confidence
of a risk long term adverse effects can be asserted include ginseng, which is unpopular
among herbalists for this reason, the endangered herb goldenseal, milk thistle, senna, against
which herbalists generally advise and rarely use, aloe vera juice, buckthorn bark and berry,
cascara sagrada bark, saw palmetto, valerian, kava, which is banned in the European Union,
St. John’s wort, Khat, Betel nut, the restricted herb Ephedra, and Guarana.There is also concern
with respect to the numerous well-established interactions of herbs and drugs. In consultation with a physician, usage of
herbal remedies should be clarified, as some herbal remedies have the potential to cause
adverse drug interactions when used in combination with various prescription and over-the-counter
pharmaceuticals, just as a patient should inform a herbalist of their consumption of
orthodox prescription and other medication.For example, dangerously low blood pressure may
result from the combination of an herbal remedy that lowers blood pressure together with prescription
medicine that has the same effect. Some herbs may amplify the effects of anticoagulants. Certain herbs as well as common fruit interfere
with cytochrome P450, an enzyme critical to much drug metabolism.In a 2018 study, FDA
identified active pharmaceutical additives in over 700 of analyzed dietary supplements
sold as “herbal”, “natural” or “traditional”. The undisclosed additives included “unapproved
antidepressants and designer steroids”, as well as prescription drugs, such as sildenafil
or sibutramine.===Labeling accuracy===
A 2013 study found that one-third of herbal supplements sampled contained no trace of
the herb listed on the label. The study found products adulterated with
contaminants or fillers not listed on the label, including potential allergens such
as soy, wheat, or black walnut. One bottle labeled as St. John’s Wort was
found to actually contain Alexandrian senna, a laxative.Researchers at the University of
Adelaide found in 2014 that almost 20 per cent of herbal remedies surveyed were not
registered with the Therapeutic Goods Administration, despite this being a condition for their sale. They also found that nearly 60 per cent of
products surveyed had ingredients that did not match what was on the label. Out of 121 products, only 15 had ingredients
that matched their TGA listing and packaging.In 2015, the New York Attorney General issued
cease and desist letters to four major U.S. retailers (GNC, Target, Walgreens, and Walmart)
who were accused of selling herbal supplements that were mislabeled and potentially dangerous. Twenty-four products were tested by DNA barcoding
as part of the investigation, with all but five containing DNA that did not match the
product labels.===Practitioners of herbalism===Herbalists must learn many skills, including
the wildcrafting or cultivation of herbs, diagnosis and treatment of conditions or dispensing
herbal medication, and preparations of herbal medications. Education of herbalists varies considerably
in different areas of the world. Lay herbalists and traditional indigenous
medicine people generally rely upon apprenticeship and recognition from their communities in
lieu of formal schooling.In some countries, formalized training and minimum education
standards exist, although these are not necessarily uniform within or between countries. In Australia, for example, the self-regulated
status of the profession (as of 2009) resulted in variable standards of training, and numerous
loosely-formed associations setting different educational standards. One 2009 review concluded that regulation
of herbalists in Australia was needed to reduce the risk of interaction of herbal medicines
with prescription drugs, to implement clinical guidelines and prescription of herbal products,
and to assure self-regulation for protection of public health and safety. In the United Kingdom, the training of herbalists
is done by state funded universities offering Bachelor of Science degrees in herbal medicine.===Government regulations===
The World Health Organization (WHO), the specialized agency of the United Nations (UN) that is
concerned with international public health, published Quality control methods for medicinal
plant materials in 1998 in order to support WHO Member States in establishing quality
standards and specifications for herbal materials, within the overall context of quality assurance
and control of herbal medicines.In the European Union (EU), herbal medicines are regulated
under the Committee on Herbal Medicinal Products.In the United States, herbal remedies are regulated
dietary supplements by the Food and Drug Administration (FDA) under current good manufacturing practice
(cGMP) policy for dietary supplements. Manufacturers of products falling into this
category are not required to prove the safety or efficacy of their product so long as they
do not make ‘medical’ claims or imply uses other than as a ‘dietary supplement’, though
the FDA may withdraw a product from sale should it prove harmful.Canadian regulations are
described by the Natural and Non-prescription Health Products Directorate which requires
an eight-digit Natural Product Number or Homeopathic Medicine Number on the label of licensed herbal
medicines or dietary supplements.Some herbs, such as cannabis and coca, are outright banned
in most countries though coca is legal in most of the South American countries where
it is grown. The Cannabis plant is used as an herbal medicine,
and as such is legal in some parts of the world. Since 2004, the sales of ephedra as a dietary
supplement is prohibited in the United States by the FDA, and subject to Schedule III restrictions
in the United Kingdom.===Scientific criticism===
Herbalism has been criticized as a potential “minefield” of unreliable product quality,
safety hazards, and potential for misleading health advice. Globally, there are no standards across various
herbal products to authenticate their contents, safety or efficacy, and there is generally
an absence of high-quality scientific research on product composition or effectiveness for
anti-disease activity. Presumed claims of therapeutic benefit from
herbal products, without rigorous evidence of efficacy and safety, receive skeptical
views by scientists.Unethical practices by some herbalists and manufacturers, which may
include false advertising about health benefits on product labels or literature, and contamination
or use of fillers during product preparation, may erode consumer confidence about services
and products.==Paraherbalism==Paraherbalism is the pseudoscientific use
of extracts of plant or animal origin as supposed medicines or health-promoting agents. Phytotherapy differs from plant-derived medicines
in standard pharmacology because it does not isolate and standardize the compounds from
a given plant believed to be biologically active. It relies on the false belief that preserving
the complexity of substances from a given plant with less processing is safer and potentially
more effective, for which there is no evidence either condition applies.Phytochemical researcher
Varro Eugene Tyler described paraherbalism as “faulty or inferior herbalism based on
pseudoscience”, using scientific terminology but lacking scientific evidence for safety
and efficacy. Tyler listed ten fallacies that distinguished
herbalism from paraherbalism, including claims that there is a conspiracy to suppress safe
and effective herbs, herbs can not cause harm, that whole herbs are more effective than molecules
isolated from the plants, herbs are superior to drugs, the doctrine of signatures (the
belief that the shape of the plant indicates its function) is valid, dilution of substances
increases their potency (a doctrine of the pseudoscience of homeopathy), astrological
alignments are significant, animal testing is not appropriate to indicate human effects,
anecdotal evidence is an effective means of proving a substance works and herbs were created
by God to cure disease. Tyler suggests that none of these beliefs
have any basis in fact.==Traditional systems=====
Africa===Up to 80% of the population in Africa uses
traditional medicine as primary health care.===Americas===
Native Americans medicinally used about 2,500 of the approximately 20,000 plant species
that are native to North America.===China===
Some researchers trained in both Western and traditional Chinese medicine have attempted
to deconstruct ancient medical texts in the light of modern science. One idea is that the yin-yang balance, at
least with regard to herbs, corresponds to the pro-oxidant and anti-oxidant balance. This interpretation is supported by several
investigations of the ORAC ratings of various yin and yang herbs.===India===In India, Ayurvedic medicine has quite complex
formulas with 30 or more ingredients, including a sizable number of ingredients that have
undergone “alchemical processing”, chosen to balance dosha.In Ladakh, Lahul-Spiti and
Tibet, the Tibetan Medical System is prevalent, also called the ‘Amichi Medical System’. Over 337 species of medicinal plants have
been documented by C.P. Kala. Those are used by Amchis, the practitioners
of this medical system.In Tamil Nadu, Tamils have their own medicinal system now popularly
called Siddha medicine. The Siddha system is entirely in the Tamil
language. It contains roughly 300,000 verses covering
diverse aspects of medicine. This work includes herbal, mineral and metallic
compositions used as medicine. Ayurveda is in Sanskrit, but Sanskrit was
not generally used as a mother tongue and hence its medicines are mostly taken from
Siddha and other local traditions.===Indonesia===In Indonesia, especially among the Javanese,
the jamu traditional herbal medicine is an age old tradition preserved for centuries. Jamu is thought to have originated in the
Mataram Kingdom era, some 1300 years ago. The bas-reliefs on Borobudur depict the image
of people grinding herbs with stone mortar and pestle, a drink seller, a physician and
masseuse treating their clients. All of these scenes might be interpreted as
a traditional herbal medicine and health-related treatments in ancient Java. The Madhawapura inscription from Majapahit
period mentioned a specific profession of herbs mixer and combiner (herbalist), called
Acaraki. The medicine book from Mataram dated from
circa 1700 contains 3,000 entries of jamu herbal recipes, while Javanese classical literature
Serat Centhini (1814) describes some jamu herbal concoction recipes.Though possibly
influenced by Indian Ayurveda systems, Indonesia’s vast archipelago holds numerous indigenous
plants not to be found in India, including plants similar to those in Australia beyond
the Wallace Line. Jamu practices may vary from region to region,
and are often not written down, especially in remote areas of the country. Although primarily herbal, some Jamu materials
are acquired from animals, such as honey, royal jelly, milk and ayam kampung eggs.==Philosophy==
Herbalists tend to use extracts from parts of plants, such as the roots or leaves, believing
that plants are subject to environmental pressures and therefore develop resistance to threats
such as radiation, reactive oxygen species and microbial attack in order to survive,
providing defensive phytochemicals of use in herbalism.==Uses of herbal medicines by animals==Indigenous healers often claim to have learned
by observing that sick animals change their food preferences to nibble at bitter herbs
they would normally reject. Field biologists have provided corroborating
evidence based on observation of diverse species, such as chickens, sheep, butterflies, and
chimpanzees. The habit of changing diet has been shown
to be a physical means of purging intestinal parasites. Lowland gorillas take 90% of their diet from
the fruits of Aframomum melegueta, a relative of the ginger plant, that is a potent antimicrobial
and apparently keeps shigellosis and similar infections at bay. Current research focuses on the possibility
that this plant also protects gorillas from fibrosing cardiomyopathy, which has a devastating
effect on captive animals.Sick animals tend to forage plants rich in secondary metabolites,
such as tannins and alkaloids. Because these phytochemicals often have antiviral,
antibacterial, antifungal, and antihelminthic properties, a plausible case can be made for
self-medication by animals in the wild.==See also

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