Kava
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| Image:Youngkava.jpg Young Piper methysticum
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| Piper methysticum G.Forst. |
Kava (Piper methysticum) is an ancient crop of the western Pacific. Other names for kava include ʻawa (Hawaii), 'ava (Samoa), yaqona (Fiji), and sakau (Pohnpei). It is also alternatively spelled kawa. The word kava is used to reffer both to the plant and the beverage produced from it.
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[edit] Preparation and consumption
Kava is prepared and consumed in a variety of ways throughout the Pacific Ocean cultures of Polynesia, Vanuatu, Melanesia and some parts of Micronesia. Traditionally kava has been prepared by either by chewing, grinding or pounding. Chewing the kava consists of macerating it in the mouth, depositing it back into a bowl, mixing with water and then straining it through the cloth-like fiber of a coconut tree. Another method is grinding in which the kava is ground by hand against a cone-shaped block of dead coral, the hand forming a makeshift mortar and the coral cone, a pestle. The moist ground kava root is combined with only a small amount of water as the fresh root releases a good deal of moisture during grinding. The last method is by pounding the kava in a large stone with a small log. Kava prepared in any of these ways is significantly more potent than unprocessed kava. The product resulting from these methods is then added to cold water and consumed as quickly as possible.
The extract is an emulsion, consisting of suspended kavalactone droplets in a starchy suspension. The taste is slightly pungent, while the distinctive aroma varies depending on whether it's been prepared from dry or fresh material, and by variety. The color is grey to tan to opaque greenish.
Various sources incorrectly state that preparation technique of mastication potentiates the psychoactive effects of kava because of the action of saliva enzymes on the plant. Although chewing kava does produce a more powerfull effect than any other form of preparation (this is due to the much finer particles produced in this method,) it is not the result of any chemical process.
The strength of prepared kava also depends on its species, freshness, and techniques of cultivation. Fresh, undried kava produces a stronger beverage than old, dried kava.
[edit] Effects
The onset of a moderate potency kava drink is 20-30 minutes, with effects usually lasting for two hours. Effects can be felt up to eight hours after ingestion.
These effects of drinking kava, in order of sensation, are slight tongue and lip numbing caused by the contraction of the blood vessels in these areas (the lips and skin surrounding may appear unusually pale); mildly talkative and euphoric behavior; anxiolytic (calming) effects, sense of well-being, clear thinking; and relaxed muscles. Sleep is often restful and there are no after-effects the next day. In Vanuatu, drinking strong kava is normally followed by a hot meal or tea. Meals consumed along with kava traditionally follow some time after the beverage so that the psychoactives are absorbed into the bloodstream more quickly.
A drink of high potency results in a faster onset with a lack of stimulation, somnolence, and then deep, dreamless sleep within 30 minutes. Unlike alcohol-induced sleep, after wakening the drinker does not experience any mental or physical after effects.
Heavy consumption of kava can produce dermatological effects ranging from light, red bumps; to heavy, scaly, ulcerous skin. Kava containes lactones that bind to skin proteins forming antigens which then lead to the allergic response. Discontinuation or reduction of consumption resolves the effects.
It is reported that many people experience rather vivid dreams after consumption of kava. [1]
Kava can also be combined with coffee to produce kavajava, the effects of which are said to combine the most pleasant qualities of each.
[edit] Pharmacology
Pharmacologically, kava is not addictive. Its active principal ingredients are the kavalactones, of which 15 have been identified and are all considered psychoactive. Only six of these kavalactones produce noticeable effects, and their concentrations can vary in kava plants. Different ratios can produce different effects.
Fresh kava root contains on average 80% water. Dried root contains approximately 43% starch, 20% fibers, 15% kavalactones, 12% water, 3.2% sugars, 3.6% proteins, and 3.2% minerals. Kavalactone content is greatest in the roots and decreases as you move up the plant. Relative concentrations of 15%, 10% and 5% have been observed in the root, stump, and basal stems, respectively.
While kava has been considered to be relatively safe, some kava herbal supplements may contribute to rare but severe hepatotoxic reactions likely due to additives (see section on safety).
[edit] Kava culture
Main article: Kava culture Image:Kava.jpg
Kava is used for a variety of purposes, medicinal, religious, political, cultural and social throughout the Pacific. These cultures have a great respect for the plant and place a high importance on it. Kava is used primariarly in social gatherings to increase amiability and to relax after a day's work. It additionally has great religious significance, being used to obtain inspiration.
[edit] Kava botany & agronomy
There are several cultivars of kava, with varying concentrations of both primary and secondary psychoactive substances. The Republic of Vanuatu is recognised as the 'home' of kava because it hosts the largest number of cultivars. The kava plant has historically been grown only in the Pacific islands of Hawaii, Federated States of Micronesia, Vanuatu, Fiji, the Samoas and Tonga. In modern times (i.e., since WW2) there has been some kava grown in the Solomon Islands, but most kava used in that country is imported. Kava is a cash crop in Vanuatu and Fiji.
The kava plant, a shrub, thrives in well-drained soils and it grows well as an understory crop (i.e., too much sunlight, especially in early growth, is deleterious). It grows naturally where rainfall is plentiful (over 2,000mm/yr). Ideal growing conditions range from 20-35 celcius degrees, and 70-100% relative humidity. The soil it is kept in should be loose to ensure plenty of air reaching the root.
Kava is unable to sexually reproduce. Female flowers are especially rare and do not produce fruit even when hand-pollinated. Its propagation is entirely due to human efforts by the method of striking.
Traditionally, plants were not harvested until they were around 4 years of age, as older plants have higher concentrations of kavalactones. However, over the past two decades farmers have been harvesting younger and younger plants--even as young as eighteen months. Older plants are not much taller (around 2m.) than younger plants; growth adds diameter to the culm and more stalks than height. A grown plant's roots can reach up to 60 centimeters in depth.
[edit] Medicinal kava
In the Western world, kava is commonly marketed as a herbal remedy to ease the symptoms of stress, anxiety, and depression.
On 15 February 2006, the Fiji Times and Fiji Live both reported that researchers at the University of Aberdeen in Scotland, and the Laboratoire de Biologie Moleculaire du Cancer in Luxembourg had discovered kava may be effective in the treatment of ovarian cancer and leukemia. Kava compounds inhibited the activation of a nuclear factor that led to the growth of cancer cells. Aberdeen University had published its findings in the journal, The South Pacific Journal of Natural Science, that kava methanol extracts had been shown to kill leukaemia and ovarian cancer cells in test tubes. The kava compounds were shown to work selectively, passing healthy cells by and targeting only cancerous cells.
Fiji Kava Council Chairman Ratu Josateki Nawalowalo welcomed the findings, saying that they would boost the kava industry. For his part, Agriculture Minister Ilaitia Tuisese called on the researchers to help persuade members of European Union to lift their ban on kava imports.
[edit] Safety
Recently, concerns have been raised about the safety of kava.<ref>Mark Blumenthal (2002). Kava safety questioned due to case reports of liver toxicity. American Botanical Council. HerbalGram. Retrieved on 2005-12-07.</ref> There have been several reports of severe liver toxicity, including liver failure in some people who have used dietary supplements containing kava extract. While a conclusive link to kava has not been established, the severity of liver damage have prompted action of many regulatory agencies. In the UK, the Medicines for Human Use (Kava-kava) (Prohibition) Order 2002 prohibits the sale, supply or import of most derivative medicinal products. Regulatory drug agencies in France and Switzerland have outlawed kava completely. The health agency of Canada issued a stop-sale order for kava in 2002. However, subsequent legislation in 2004 rendered the legal status of kava in question.<ref>Heather S. Boon & Albert H.C. Wong (2003-11-25). Kava: a test case for Canada's new approach to natural health products. Canadian Medical Association. Retrieved on 2006-07-10.</ref> The United States CDC has released a report<ref>United States Centers for Disease Control and Prevention (2002). "Hepatic Toxicity Possibly Associated with Kava-Containing Products --- United States, Germany, and Switzerland, 1999—2002". Morbidity & Mortality Weekly Report 51(47): 1065–1067. Retrieved on 2005-09-16.</ref> expressing reservations about the use of kava and its possibly adverse side effects (specifically severe liver toxicity), as has the Food and Drug Administration (FDA)<ref>Center for Food Safety and Applied Nutrition (2002). "Kava-Containing Dietary Supplements May Be Associated with Severe Liver Injury". United States Food and Drug Administration. Retrieved on 2005-06-16.</ref>. Some counter that the cases resulting in the liver toxicity included concomitant use of alcohol or other drugs<ref>Schmidt, Mathias (2003-05-28). Is kava really hepatotoxic? An analysis of the known data on adverse effects of kava preparations on the liver. Universität Münster. Retrieved on December 3, 2005. (Download PDF 1.87MB)</ref>. Another claim is that kava extracts used by patients experiencing liver toxicity were made with solvents other than the traditional water and that the whole plant was used rather than just the roots. Not a single conclusive case of adverse liver effects has ever been reported amongst natives who have used it for hundreds of years. The issue is controversial and debate is fuelled by economic interests of kava-exporting nations of the Pacific Islands as well as disagreements between the medical establishment and proponents of herbal and natural medicine.
There is ongoing research into the causes of kava liver toxicity and why it apparently does not affect traditional kava users. One study at the University of Hawaii at Manoa found that an alkaloid of the kava plant called pipermethystine may be responsible for the liver toxicity cases, based on its effects on liver cells in vitro<ref>"UH scientists may have solved kava mystery", Honolulu Advertiser, 2003-04-07. Retrieved on 2005-10-27.</ref>. This alkaloid is found primarily in stem peelings and leaves of the plant, but is not present in the roots. Users of kava in the South Pacific have traditionally discarded the peelings and leaves, using only the roots for the consumed product. Industrial use of peelings and leaves is because of the expected profit gain. Since traditional users avoided consumption of these parts of the plant, this may explain the extensive use of kava in the Pacific with no ill effects, whereas the novel use in Europe and America witnessed cases of liver toxicity due to improper use of the plant.
The German Federal Institute for Drugs and Medical Devices (BfArM) that in 2002 temporarily inactivated kava registrations, asked the producers to provide new clinical data until June 2007, in which case a reinstitution of the kava products on the market might again be possible.<ref>American Botanical Council. German Government Reconsiders Kava. Retrieved on 2006-05-12.</ref><ref>University of the South Pacific. USP plays a major role in the partial lifting of the Kava ban in Germany. Retrieved on 2006-05-12.</ref>
A New Zealand committee who also looked at the same evidence, commented in their summary: "A comparison with paracetamol-associated hepatotoxicity, results in the conclusion that these potential risks for kava are dramatically less than that of a popular non prescription drug widely sold through grocery outlets."<ref>New Zealand association of medical herbalists (2005). Submission on proposed reclassification of kava as a prescription medicine (PDF). Retrieved on 2006-05-12.</ref> The NZ government is currently only looking at the possibility of a suitable advisory label standard to go on kava products.
Dr. Ifereimi Waqainabete of the Fiji School of Medicine told the conference of the Pacific Islands Surgeons Association (7 March 2006) that kava adversely affected a person's nervous system. Students under the influence of Kava had proved unable to correctly complete a symbol test, he claimed.
The Australian Therapeutic Goods Administration has recommended that no more than 250mg of kavalactones be taken in a 24 hour period.<ref>Kava fact sheet. Therapeutic Goods Administration, Government of Australia (April 2005). Retrieved on 2006-07-10. (Download PDF 44KB)</ref>
[edit] References
- Lebot, Vincent et al. Kava: The Pacific Drug New Haven: Yale University Press, 1992. ISBN 0-300-05213-8
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[edit] External links
- Farmers Bookshelf - Information on Tropical Crop Production in Hawaiʻi (Site has javascript navigation and kava (ʻawa) pages cannot be directly linked: click on "nutraceuticals", then "'Awa".)
- Hawaiʻi Pacific Islands Kava Festival - An education, cultural event held in Hawaii sponsored by the nonprofit, ʻAwa Development Council
- Kava Ban documents
- Lycaeum: Includes list of isolated chemicals
- How to make traditional-style kava drink
- Erowid's Kava vault
- Kava news page - Alcohol and Drugs History Society
- Kava Testimonialsde:Kava
es:Piper methysticum fr:Kava hu:Kava ja:カバ (薬物) no:Kava pl:Kava kava ru:Перец опьяняющий
