Herbalism, also known as Herbal medicine and phytotherapy, is a folk and traditional medicinal practice based on the use of plants and plant extracts.
Finding healing powers in plants is an ancient idea. People in all continents have long used hundreds, if not thousands, of indigenous plants for treatment of various ailments dating back to prehistory. These plants are still widely used in ethnomedicine around the world.
The first generally accepted use of plants as healing agents were depicted in the cave paintings discovered in the Lascaux caves in France, which have been Radiocarbon dated to between 13,000 - 25,000 BCE.
Anthropologists theorize that over time, and with trial and error, a small base of knowledge would have been acquired within early tribal communities. As this knowledge base expanded over the generations, the specialized role of the shaman emerged. The process would likely have occurred in varying manners within a wide diversity of cultures.
Plants have an almost limitless ability to synthesize aromatic substances, most of which are phenols or their oxygen-substituted derivatives such as tannins. Most are secondary metabolites, of which at least 12,000 have been isolated, a number estimated to be less than 10% of the total. In many cases, these substances (esp. alkaloids) serve as plant defense mechanisms against predation by microorganisms, insects, and herbivores. Many of the herbs and spices used by humans to season food yield useful medicinal compounds.
The use of and search for drugs and dietary supplements derived from plants have accelerated in recent years. Pharmacologists, microbiologists, botanists, and natural-products chemists are combing the Earth for phytochemicals and leads that could be developed for treatment of various diseases. In fact, many modern drugs have been derived from plants.
The use of herbs to treat disease is almost universal among non-industrialized societies. A number of traditions came to dominate the practice of herbal medicine in the Western world at the end of the twentieth century:
- The Western, based on Greek and Roman sources,
The Ayurvedic from India, and
Chinese herbal medicine (Chinese herbology).
Many of the pharmaceuticals currently available to Western physicians have a long history of use as herbal remedies, including opium, aspirin, digitalis, and quinine.
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Biological background
All plants produce chemical compounds as part of their normal metabolic activities. These can be split into primary metabolites, such as sugars and fats, found in all plants, and secondary metabolites found in a smaller range of plants, some only in a particular genus or species.
The autologous functions of secondary metabolites are varied. For example, as toxins to deter predation, or to attract insects for pollination. It is these secondary metabolites which can have therapeutic actions in humans and which can be refined to produce drugs. Some examples are inulin from the roots of dahlias, quinine from the cinchona, morphine and codeine from the poppy, and digoxin from the foxglove.
As of 2004, the National Center for Complementary and Alternative Medicine started to fund clinical trials into the effectiveness of herbal medicine.[1]
Surveys of a scientific approach to herbal medicine can be found in the books Evidence-based herbal medicine,[2] and Herbal and traditional medicine: molecular aspects of health.[3]
Popularity
A survey released in May 2004[4] by the National Center for Complementary and Alternative Medicine focused on who used complementary and alternative medicines (CAM), what was used, and why it was used. The survey was limited to adults age 18 years and over during 2002 living in the United States. According to this recent survey, herbal therapy, or use of natural products other than vitamins and minerals, was the most commonly used CAM therapy (18.9%)[5] when all use of prayer was excluded.
Herbal remedies are most common in Europe. In Germany, the term apothecary (Apotheke) is still used, and next to prescription drugs one can order essential oils, herbal extracts, or herbal teas. It is even seen as a preferred treatment over the unnecessary overuse of industrialized production of chemical medication.
Types of herbal medicine
Medicinal plants can be used by anyone, for example as part of a salad, an herbal tea or supplement, although some herbs considered dangerous are restricted from sale to the public. Sometimes such herbs are provided to professional herbalists by specialist companies. Many herbalists, both professional and amateur, often grow or wildcraft their own herbs. Many common weeds have medicinal properties (e.g. dandelion)
Medicinal herbs can be used in various forms:
Herbal teas
There are two methods of making herbal teas, infusion and decoction. Infusion is steeping lighter parts of the plant (leaves, flowers, light stems) in boiled water for several minutes. Decoction is boiling tougher parts, such as roots or bark for a longer period of time. Herbal teas are often used as a home remedy, and as an alternative to tea and coffee.
Herbal tinctures
Steeping a medicinal plant in alcohol extracts the alcohol-soluble principles into a liquid form that can be stored for long periods. Herbalists may mix several herbal tinctures to form an individualized prescription for each patient. Plant tinctures are also the basis for many homeopathic medicines.
Fluid extracts
Fluid extracts are stronger than herbal tinctures, and can be made with alcohol or glycerin.
Herbal poultices
Poultices are a solid, vegetable fat based mixture used externally. They have the shortest life span of any herbal remedy and must be made fresh for every use.
Powdered herbs and tablets
Herbs that are dried and (sometimes) certain parts are separated out then diced to powder fine consistency. Powered matter can then be compressed or put in an empty pill coating to form a tablet
Herbal creams and ointments
An ointment usually is mixed with beeswax (or something similar) to make it more applicable to outside the body, such as on a cut or scrape.
Essential oils
Extraction of volatile liquid plant materials and other aromatic compounds from plants gives essential oils. These plant oils may be used internally in some forms of herbal medicine as well as in aromatherapy and generally for their perfume, although their medicinal use as a natural treatment (alternative medicine) has proved highly efficacious in the treatment of headache and muscle pain[6], joint pain[7] and certain skin diseases[8]
Herbal supplements
Herbal supplements tend to be commercial products in tablet or capsule form manufactured and marketed by the health food industry for sale in retail outlets to the general public, although there are some types that are sold only to healthcare practitioners for prescription. Herbal supplements are often standardized to contain stated levels of active phytochemicals. Some herbalists may not agree with the standardization of active ingredients, preferring instead to use the whole plant.
Examples of herbal medicine
There are hundreds of herbal remedies. An experienced practitioner can offer a comprehensive holistic approach to health. Examples of some commonly used herbal medicines:
- Artichoke and several other plants reduced total
serum cholesterol levels in preliminary studies.[9]
Black cohosh and other plants that contain phytoestrogens (plant molecules with estrogen activity) have some benefits for treatment of symptoms resulting from menopause.[10]
Echinacea extracts limit the length of colds in some clinical trials, although some studies have found it to have no effect.[11]
Garlic lowers total cholesterol levels, mildly reduces blood pressure, reduces platelet aggregation, and has antibacterial properties.[12]
Grapefruit seed extract as a natural antimicrobial has minimal effectiveness as an anti-bacterial, anti-parasitic, and anti-fungal herb.[13][14][15][16][17]
Nigella sativa (Black cumin) is a general medicinal plant used for diverse ailments such as cough, pulmonary infections, asthma, influenza, allergy, hypertension and stomach ache. The seeds are considered carminative, stimulant, diuretic and galactogogue. It is often taken with honey. Seed powder or oil is externally applied for eruptions of skin.
Peppermint tea for problems with the digestive tract, including irritable bowel syndrome and nausea.
Rauvolfia Serpentina, used extensively in India for sleeplessness, anxiety, and high blood pressure. The first proven allopathic medicine for high blood pressure was extracted from this herb.
St John's wort, has yielded positive results, proving more effective than a placebo for the treatment of mild to moderate depression in some clinical trials.[18]
Valerian root can be used to treat insomnia.
Dangers
A common misconception about herbalism and the use of 'natural' products in general, is that 'natural' equals safe. However many plants have chemical defence mechanisms against predators that can have adverse or lethal effects on humans. Examples are poison hemlock and nightshade, which can be deadly. Herbs can also have undesirable side-effects just as pharmaceutical products can. These problems are exacerbated by lack of control over dosage and purity. Furthermore, if given in conjunction with drugs, there is danger of 'summation', where the herb and the drug have similar actions and add together to make an 'overdose'. In animals, there are other dangers. There may be residues in food from farm animals (e.g. eggs, milk, meat) or danger of 'doping' in competition animals. The latter may also apply to human athletes.
Effectiveness
As noted above, there have been scientific studies which show that certain plant products can cure or prevent certain diseases, and these products or pharmaceutical drugs derived from them are patented by pharmaceutical companies and sold for high profit in modern Western medicine. Pharmaceutical firms argue that the individual should not have control over their health to the point of experimenting with "potentially hazardous materials".
Most herbal traditions have accumulated knowledge without modern scientific controls to distinguish between the placebo effect, the body's natural ability to heal itself, and the actual benefits of the herbs themselves. This is because most knowledge also pre-dates modern discoveries in human physiology and biochemistry. In fact, much knowledge dates back to medieval Europe, and was exterminated along with the witches during the burnings. Together the church and male-dominated 19th and 20th century medicine discredited much of this knowledge, and most has been lost.
There is a danger that herbal remedies will be used in place of other medical treatments which have been scientifically proven to be safe and effective, resulting in the development or worsening of a medical condition which could have been better prevented or treated. There is also a danger that an herbal remedy may itself cause harm which is unanticipated due to a lack of a full understanding of its composition and biochemical effects.
Name confusion
The common names of herbs (folk taxonomy) may not reflect differences in scientific taxonomy, and the same (or a very similar) common name might group together different plant species with different effects. For example, in 1993 in Belgium, in a TCM remedy for weight loss, one herb (Stephania tetrandra) was swapped for another (Aristolochia fangchi) whose name in Chinese was extremely similar but which contained higher levels of a renal toxin, aristolochic acid; this quid pro quo resulted in 105 cases of kidney damage. [19] [20]
Standards and quality control
The legal status of herbal ingredients varies by country. For example, Ayurvedic herbal products may contain levels of heavy metals that are considered unsafe in the U.S., but heavy metals are considered therapeutic in Ayurvedic medicine.
In the United States, most herbal remedies are regulated as dietary supplements. Many herbs for home use can be grown in a small home garden too.
Medical interaction
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. 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. In particular, many herbs should be avoided during pregnancy.[21] However, most herbal books alert the reader to necessary precautions.
Not all physicians may be familiar with the effects of different types of herbal medicine, but general practitioners should be able to refer patients to a specialist, or investigate the medical literature on their behalf.
See also
References
- ^ NIH Institute and Center Resources, National Institute of Health.
- ^ "Evidence-based herbal medicine" edited by Michael Rotblatt, Irwin Ziment; Philadelphia: Hanley & Belfus, 2002
- ^ "Herbal and traditional medicine: molecular aspects of health", edited by Lester Packer, Choon Nam Ong, Barry Halliwell; New York: Marcel Dekker, 2004.
- ^ More Than One-Third of U.S. Adults Use Complementary and Alternative Medicine Press release, May 27, 2004. National Center for Complementary and Alternative Medicine
- ^ Barnes, P M; Powell-Griner E, McFann K, Nahin R L (2004-05-27). Complementary and Alternative Medicine Use Among Adults: United States, 2002 (PDF). Advance data from vital and health statistics; no 343 pp. 20. National Center for Health Statistics. 2004. Retrieved on September 16, 2006. (See table 1 on page 8).
- ^ Herbal Alternatives to Drugs in Pain Management, Part II (2006). Retrieved on October26, 2006.
- ^ EFFECT OF A PROPRIETARY HERBAL MEDICINE ON THE RELIEF OF CHRONIC ARTHRITIC PAIN: A DOUBLE-BLIND STUDY (2006). Retrieved on October26, 2006.
- ^ White, H; LMacCal (2006-10-22). Herbal Medicine and wart removal, hemorrhoids treatment and herpes prevention - without drugs: Canada, 2006 (english). doc 102. various. Retrieved on October 26, 2006.
- ^ Thompson Coon JS, Ernst E. "Herbs for serum cholesterol reduction: a systematic view." J Fam Pract. 2003 Jun;52(6):468-78. PMID 12791229
- ^ Kronenberg F, Fugh-Berman A. "Complementary and alternative medicine for menopausal symptoms: a review of randomized, controlled trials." Ann Intern Med. 2002 Nov 19;137(10):805-13. PMID 12435217 annals.org (133 K PDF file) Full text article
- ^ Block KI, Mead MN. "Immune system effects of echinacea, ginseng, and astragalus: a review." Integr Cancer Ther. 2003 Sep;2(3):247-67. PMID 15035888
- ^ www.herbaled.org Garlic
- ^ Ganzera M, Aberham A, Stuppner H. Development and validation of an HPLC/UV/MS method for simultaneous determination of 18 preservatives in grapefruit seed extract. Institute of Pharmacy, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria. J Agric Food Chem. 2006 May 31;54(11):3768-72. PMID 16719494
- ^ Takeoka, G., Dao, L., Wong, R.Y., Lundin, R., Mahoney N. Identification of benzethonium chloride in commercial grapefruit seed extracts. J Agric Food Chem. 2001 49(7):3316–20. PMID 11453769
- ^ von Woedtke, T., Schlüter, B., Pflegel, P., Lindequist, U.; Jülich, W.-D. Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained. Pharmazie 1999 54:452–456. PMID 10399191
- ^ Sakamoto, S., Sato, K., Maitani, T., Yamada, T. Analysis of components in natural food additive “grapefruit seed extract” by HPLC and LC/MS. Bull. Natl. Inst. Health Sci. 1996, 114:38–42. PMID 9037863
- ^ Takeoka, G.R., Dao, L.T., Wong, R.Y., Harden L.A. Identification of benzalkonium chloride in commercial grapefruit seed extracts. J Agric Food Chem. 2005 53(19):7630–6. PMID 16159196
- ^ Gupta RK, Moller HJ. "St. John's Wort. An option for the primary care treatment of depressive patients?" Eur Arch Psychiatry Clin Neurosci. 2003 Jun;253(3):140-8. PMID 12904978
- ^ Vanherweghem JL, Depierreux M, Tielemans C, et al. "Rapidly progressive interstitial renal fibrosis in young women: association with slimming regimen including Chinese herbs." Lancet. 1993 Feb 13;341(8842):387-91.
- ^ Vanhaelen M, Vanhaelen-Fastre R, But P, Vanherweghem JL. "Identification of aristolochic acid in Chinese herbs." Lancet. 1994 Jan 15;343(8890):174. PMID 7904018
- ^ gaiagarden.com Herbs to avoid during pregnancy
External links
Regulation
- Website of the National Herbalists Association of Australia
- National Institute for Medical Herbalists Website for the governing body in the United Kingdom
- An overview of medicinal plants from the Science Creative Quarterly
Neutral
- Center for Complementary and Alternative Medicine (National Institutes of Health)
- Searchable database on Traditional Chinese Herbs (www.rootdown.us)
- American Herbalist Guild
Criticism
- New England Journal of Medicine editorial about the risks of alternative medicine
- University of Maryland site about alternative medicine: uses, possible prescription drug interactions, and possible nutrient depletions
- Herbal supplements not child's play - Cnn news article
- Herbal Mythology - By Steven Novella MD
- Selling Suppliments - By Steven Novella MD